Uni-Joint Formula by Douglas Laboratories

POSSIBLY INEFFECTIVE

• Night vision. Most research suggests that oral bilberry does not improve night vision in healthy individuals. Details: There is contradictory evidence about the effectiveness of bilberry for improving night vision; however, much of the research is of poor quality. In general, the most rigorous research shows that bilberry is not effective for improving night vision in healthy individuals (8139,9739,14280,35446). Whether bilberry can improve night vision in patients with night blindness is unclear.

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Age-related cognitive decline. Oral bilberry has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical study of elderly Norwegian males with subjective cognitive impairment shows that drinking 330 mL of bilberry and red grape juice twice daily for 9 weeks does not improve measures of memory or motor skills when compared with placebo (110641).
• Age-related macular degeneration (AMD). Although there has been interest in using oral bilberry for AMD, there is insufficient reliable information about the clinical effects of bilberry for this purpose.
• Asthenopia (eye strain). Small clinical studies suggest that oral bilberry fruit extract may improve objective measures of asthenopia, but it is unclear if oral bilberry improves subjective symptoms of asthenopia. Details: Two small clinical studies in adults who report general eye strain or those who look at computer or other display screens at work for long periods of time show that taking bilberry-derived anthocyanins 43.2 mg daily for 6 weeks or bilberry extract 240 mg daily for 12 weeks improves objective measures of eye strain after staring at computer screens when compared with placebo (103190,104195). However, bilberry extract did not improve subjective measures of eye strain in the study that evaluated these outcomes (104195). This study may have been underpowered to detect significant differences between groups. Bilberry has also been evaluated in combination with other ingredients for improving eye strain. A small clinical trial in patients with eye strain shows that a combination of fish oil, lutein, and bilberry extract containing bilberry anthocyanidins 59 mg, taken daily for 4 weeks, reduces dry eye, lower back pain, shoulder stiffness, and stuffy head when compared with placebo (35470). It is unclear if these effects are due to bilberry, other ingredients, or the combination.
• Atherosclerosis. Although there has been interest in using oral bilberry for atherosclerosis, there is insufficient reliable information about the clinical effects of bilberry for this purpose.
• Cataracts. Although there has been interest in using oral bilberry for cataracts, there is insufficient reliable information about the clinical effects of bilberry for this purpose.
• Chronic venous insufficiency (CVI). It is unclear if oral bilberry is beneficial in patients with CVI. Details: One small clinical study in patients with CVI shows that taking bilberry extract containing anthocyanins 173 mg daily for 30 days reduces symptoms of CVI when compared with placebo (35510).
• Diabetes. It is unclear if oral bilberry is beneficial in patients with diabetes. Details: One small clinical trial in patients with type 2 diabetes shows that taking a specific extract of bilberry fruit (Mirtoselect, Indena S.p.A) 470 mg once, prior to taking an oral glucose tolerance test, lowers plasma glucose levels when compared with placebo (91507). However, a small crossover trial in Chinese patients with type 2 diabetes shows that taking bilberry fruit extract 700 mg twice daily for 4 weeks does not improve glycated hemoglobin (HbA1c), body weight, blood pressure, or lipid levels when compared with placebo (104194). The validity of the HbA1c-related findings is limited due to the short study duration.
• Diabetic retinopathy. It is unclear if oral bilberry is beneficial in patients with diabetic retinopathy. Details: One small clinical trial in adults with diabetic and hypertensive retinopathy shows that taking bilberry fruit extract 160 mg daily for 6 months, in addition to standard management, improves edema and measures of retinal circulatory health when compared with standard management alone. Bilberry in the form of a generic, commercially available product appears to produce less dramatic improvements than a branded formulation (Mirtoselect, Indena S.p.A.) containing matching anthocyanin content. This specific product also reduced flow velocity in those with high-flow, diabetic retinopathy when compared with either the generic bilberry extract or standard management alone (97032).
• Dry eye. Oral bilberry has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical study in patients with severe dry eye symptoms suggests that taking bilberry extract 600 mg and docosahexaenoic fish oil 240 mg once daily for 3 months may modestly improve measures of tear quality and patient-reported scores for dry eye symptoms when compared with control (112415). However, the validity of these results is limited by the lack of a statistical comparison between groups. Additionally, it is unclear if these effects are due to bilberry, fish oil, or the combination.
• Dysmenorrhea. It is unclear if oral bilberry is beneficial in patients with dysmenorrhea. Details: One small clinical study in patients with dysmenorrhea shows that a specific bilberry product (Tegens) containing bilberry anthocyanoside 160 mg, taken twice daily beginning 3 days prior to menses and continuing for 8 days, reduces pelvic pain, lumbosacral pain, breast pain, nausea, vomiting, and headache when compared with placebo (35512).
• Exercise-induced muscle soreness. It is unclear if oral bilberry is beneficial for reducing exercise-induced muscle soreness. Details: A small clinical study in trained athletes shows that drinking 200 mL of bilberry juice, containing about 744 mg phenols and 80 mg anthocyanins, twice daily for 5 days prior to running a half-marathon modestly worsens muscle soreness immediately after the run when compared with placebo. There was no longer a difference in muscle soreness between groups within 1-2 days after the run (99540).
• Glaucoma. Small clinical studies suggest that oral bilberry fruit extract, when taken with maritime pine extract, may lower intraocular pressure in patients with glaucoma. It is unclear if oral bilberry alone is beneficial in patients with glaucoma. Details: One small, uncontrolled clinical trial in Japanese patients with open-angle glaucoma shows that taking a specific product (Sante Glagenox, Saten Pharmaceutical Co. Ltd.) containing bilberry fruit extract 90 mg and maritime pine extract 40 mg daily for 4 weeks reduces intraocular pressure by 8.7% when compared to baseline (104192). Another small clinical study in patients with high intraocular pressure shows that taking a specific product (Mirtogenol) containing bilberry fruit extract (Mirtoselect, Indena S.p.A.) 80 mg and maritime pine extract (Pycnogenol, Horphag Research) 40 mg twice daily for 6 months lowers intraocular pressure and improves intraocular blood flow when compared with no treatment (35456). It is unclear if these findings are due to bilberry, maritime pine, or the combination. A retrospective chart review of patients with normal tension glaucoma has found that taking bilberry anthocyanin 60 mg twice daily for at least 12 months is associated with improvements in visual function when compared to pretreatment (35472).
• Hemorrhoids. Although there has been interest in using oral bilberry for hemorrhoids, there is insufficient reliable information about the clinical effects of bilberry for this purpose.
• Hyperlipidemia. It is unclear if oral bilberry is beneficial in patients with hyperlipidemia. Details: A small clinical study in adults with hyperlipidemia shows that taking bilberry-derived anthocyanins 320 mg daily for 4 weeks does not improve total cholesterol, low-density lipoprotein (LDL) cholesterol, high density lipoprotein (HDL) cholesterol, or triglyceride levels. Further, no improvements in other biomarkers of cardiovascular disease were reported (110640). The validity of this study is limited by its short duration.
• Hypertension. Oral bilberry has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: One small clinical study in adults with hypertension shows that consuming 500 mL of a juice containing bilberry, red grape, and chokeberry, with or without black currant (MANA Blue, TINE SA), daily for 12 weeks does not improve blood pressure when compared with placebo (92371).
• Hypertensive retinopathy. It is unclear if oral bilberry is beneficial in patients with hypertensive retinopathy. Details: One small clinical trial in adults with diabetic and hypertensive retinopathy shows that taking bilberry fruit extract 160 mg daily for 6 months, in addition to standard management, improves edema and measures of retinal circulatory health when compared with standard management alone. Bilberry in the form of a generic, commercially available product appears to produce less dramatic improvements than a branded formulation (Mirtoselect, Indena S.p.A.) containing matching anthocyanin content. This specific product also increased flow velocity for those with ischemic, hypertensive retinopathy when compared with either the generic bilberry extract or standard management alone (97032).
• Impaired glucose tolerance (prediabetes). Oral bilberry has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical study in adults with impaired glucose tolerance and two markers of metabolic syndrome shows that consuming a diet high in whole grain products, fatty fish, and bilberries three times daily for 12 weeks reduces levels of plasma glucose when compared to baseline (35468). However, it is unclear if these findings are due to bilberry, another component of the diet, or the combination.
• Irritable bowel syndrome (IBS). Oral bilberry has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: One small clinical trial in adults with IBS shows that consuming a formula containing powdered bilberry fruit, aerial agrimony parts, cinnamon quills, and slippery elm bark modestly improves bowel movement frequency and reduces symptoms such as abdominal pain, bloating, flatulence, and straining when compared to baseline (35462). It is unclear if these findings are due to bilberry, other ingredients, or the combination.
• Metabolic syndrome. It is unclear if oral bilberry is beneficial in patients with metabolic syndrome. Details: One small clinical study in patients with metabolic syndrome shows that consuming a diet containing 400 grams of fresh bilberries daily does not affect body weight, glucose metabolism, or lipid metabolism when compared with a control diet (35473).
• Myopia. It is unclear if oral bilberry is beneficial in patients with myopia. Details: One small clinical trial in adults with myopia shows that a specific fermented bilberry fruit extract (Fermented Blueberry, Ajinomoto, Co., Inc.) 200 mg, taken twice daily for 4 weeks, improves night vision as well as the eye's ability to adjust focus when compared with placebo. The amplitude of accommodation was also significantly increased from 4.62 to 5.33 (91505).
• Obesity. It is unclear if oral bilberry is beneficial in patients with obesity. Details: One small clinical study in obese and overweight females shows that consuming 100 grams of frozen, whole bilberries daily for 33-35 days decreases weight and waist circumference when compared to baseline (35463). The validity of these findings is limited by the lack of a comparator group.
• Osteoarthritis. Although there has been interest in using oral bilberry for osteoarthritis, there is insufficient reliable information about the clinical effects of bilberry for this purpose.
• Ulcerative colitis. It is unclear if oral bilberry is beneficial in patients with ulcerative colitis. Details: One small, open-label clinical study in adults with mild-to-moderate ulcerative colitis shows that consuming sieved bilberries and concentrated bilberry juice (Symrise GmbH & Co) 160 grams daily for 6 weeks induces remission in 46% of patients. Furthermore, 91% of patients achieved remission at the end of treatment, and 72% of patients achieved remission at the end of the study (91506). The validity of these findings is limited by the lack of a comparator group.
• Urinary tract infections (UTIs). Although there has been interest in using oral bilberry for UTIs, there is insufficient reliable information about the clinical effects of bilberry for this purpose.
• Varicose veins. Although there has been interest in using oral bilberry for varicose veins, there is insufficient reliable information about the clinical effects of bilberry for this purpose. More evidence is needed to rate bilberry for these uses.

(Read more about BILBERRY)

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Laser skin resurfacing. It is unclear if topical bovine cartilage is beneficial for recovery after laser resurfacing of the facial skin. Details: A small clinical study in patients undergoing laser resurfacing of the facial skin shows that using a specific ointment containing powdered bovine cartilage 10% (Catrix 10) every 2 hours for 24 hours following the procedure and then every 4 hours thereafter for 7 days reduces laser-induced erythema, swelling, and erosion when compared with a petrolatum-based ointment (Aquaphor) (36960).
• Osteoarthritis. It is unclear if subcutaneous or intramuscular administration of bovine cartilage is beneficial in patients with osteoarthritis; the available research is conflicting. Details: Clinical research on the use of intramuscular bovine cartilage for osteoarthritis is conflicting (8242,92771,92772,92773). Some preliminary clinical research in patients with osteoarthritis shows that intramuscular administration of a specific bovine cartilage-bone marrow complex (Rumalon, Robapharm) 2 mL three times weekly for 8 weeks, repeated 3 times each year for the first year and 2-3 times each year thereafter for up to 3 years, improves pain and mobility in some patients (92772,92773). However, other research shows that this effect is not long lasting, with no significant differences between bovine cartilage-bone marrow complex and placebo after 5 years of treatment (92771).
• Wound healing. It is unclear if topical bovine cartilage is beneficial for wound healing. Details: Preliminary clinical research shows that topical application of bovine tracheal cartilage from calves is more effective for accelerating wound healing when compared with adult and fetal bovine tracheal cartilage preparations (92750). However, it is unclear how this compares to control or standard treatment. More evidence is needed to rate bovine cartilage for these uses.

(Read more about BOVINE CARTILAGE)

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Allergic rhinitis (hay fever). Although there has been interest in using oral bromelain for allergic rhinitis, there is insufficient reliable information about the clinical effects of bromelain for this condition.
• Aromatase inhibitor-induced arthralgia. Oral bromelain has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical study in patients with aromatase inhibitor-induced arthralgia shows that taking a specific combination product (Opera, Gam Farma), providing bromelain 20 mg, alpha-lipoic acid 240 mg, Boswellia serrata 40 mg, and methylsulfonylmethane 200 mg, daily for 6 months reduces arthralgia symptoms when compared to baseline (109570). The validity of these findings is limited by a lack of placebo control group. Further, it is unclear if these findings are due to bromelain, other ingredients, or the combination.
• Burns. Preliminary clinical research shows that topical bromelain is beneficial for burn debridement. It is unclear if topical bromelain is beneficial for scar prevention. Details: Preliminary clinical research and chart reviews show that gels formulated with proteolytic enzymes derived from bromelain (Debridase or NexoBrid, MediWound Ltd.), applied under an occlusive dressing for 4 hours, help debride burns, including chemical and electrical burns, in children and adults (18275,91113,103297,108149). However, only one of these studies compared the bromelain-based enzymatic debridement product to standard of care. In this study, which included surgical excision or non-surgical debridement, bromelain-derived gel decreased the time to complete debridement by 6.5 days, reduced the risk of surgical excision by 65%, and reduced the risk for autografts by 48%. However, in the long-term, there appeared to be no difference in quality of life or scarring between groups (91113).
• Cancer. Although there has been interest in using oral bromelain for cancer, there is insufficient reliable information about the clinical effects of bromelain for this condition.
• Chemotherapy-induced peripheral neuropathy. Oral bromelain has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical study in adults with chemotherapy-induced peripheral neuropathy shows that taking a specific product (Opera, Gamfarma s.r.l.) containing bromelain 20 mg, alpha-lipoic acid 240 mg, methylsulfonylmethane (MSM) 200 mg, and boswellia 40 mg daily for 12 weeks reduces overall pain when compared with baseline (96449). The validity of these findings is limited by the lack of a control group. Additionally, it is not clear if benefit is due to alpha-lipoic acid, the other ingredients, or the combination.
• Diabetes. Oral bromelain has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small observational study in patients with a family history of type 1 diabetes found that taking a specific product (Mucos Pharma) containing bromelain 90 mg. rutin 100 mg, and trypsin 48 mg daily for 24 months is not associated with reduced incidence of type 1 diabetes at 8 years (99472).
• Diabetic foot ulcers. Although there has been interest in using topical bromelain for diabetic foot ulcers, there is insufficient reliable information about the clinical effects of bromelain for this condition.
• Exercise-induced muscle soreness. It is unclear if oral bromelain is beneficial for preventing exercise-induced muscle soreness. Details: One small clinical study shows that taking bromelain 300 mg three times daily, immediately following an intense exercise regimen, does not reduce delayed onset muscle soreness and has no effect on pain, flexibility, or skeletal weakness when compared with either ibuprofen 400 mg three times daily or placebo (10622). However, a small clinical study shows that taking a combination protease tablet containing bromelain 50 mg, trypsin 75 mg, papain 50 mg, amylase 10 mg, lipase 10 mg, lysosome 10 mg, and chymotrypsin 2 mg, four times in one day before downhill running, can improve recovery of contractile muscle function and decrease muscle soreness when compared with placebo (67838). It is unclear if these effects are due to bromelain, other ingredients, or the combination.
• Exercise-induced respiratory infections. Oral bromelain has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research in non-elite male runners shows that taking a combination product (Wobenzym Plus, Mucos Pharma) providing bromelain 540-1080 mg, rutin 600-1200 mg, and trypsin 288-576 mg daily for 3 weeks, starting one week before a marathon, does not reduce the risk of a post-race respiratory tract infection when compared with placebo (96766).
• Kidney stones (nephrolithiasis). It is unclear if oral bromelain is beneficial for kidney stone expulsion. Details: Observational research in patients with 4-10 mm kidney stones found that adding bromelain to tamsulosin is associated with a 12% increased rate of spontaneous stone expulsion when compared to tamsulosin alone (100752).
• Knee pain. It is unclear if oral bromelain is beneficial for knee pain. Details: Preliminary clinical research shows that taking bromelain (Bromelin, Lichtwer Pharma Ltd.) orally for 30 days can reduce mild, acute (duration of less than 3 months) knee pain in otherwise healthy patients when compared to baseline. A daily dose of 400 mg seems to be more effective than 200 mg daily for relieving pain, stiffness, and physical function of the knee, with reductions in symptom scores of 59% and 41%, respectively (11457).
• Lymphedema. Oral bromelain has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Some clinical research in patients who have undergone a mastectomy shows that taking a specific combination product containing bromelain, rutin, pancreatin, papain, trypsin, and chymotrypsin (Wobenzym N, Mucos Pharma) daily for 7 weeks reduces arm swelling associated with lymphedema when compared with diuretics (24560). Other preliminary clinical research in patients with primary or secondary lymphedema of the upper or lower limbs shows that taking a different combination product containing bromelain 100 mg, rutin 300 mg, and sweet clover 100 mg daily for 6 months decreases pitting, limb volume, pain, and quality of life when compared to baseline (103298). The validity of these results is limited by the lack of a control group. Additionally, it is unclear if these findings are due to bromelain, other ingredients, or the combination.
• Multiple sclerosis (MS). Oral bromelain has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A preliminary clinical study in patients with relapsing-remitting MS shows that taking an enzyme combination containing bromelain 90 mg, rutin 100 mg, and trypsin 48 mg per tablet for at least 3 months does not affect the progression of disability, relapse rate, or central nervous system lesions when compared with placebo (99468). The validity of these results is limited by the short duration of treatment.
• Ocular floaters. Oral bromelain has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A moderate-sized clinical study in patients with spontaneous symptomatic vitreous opacities (ocular floaters) shows that taking oral mixed fruit enzyme capsules containing bromelain 190 mg, papain, and ficin once, twice, or three times daily for 3 months eliminates floaters in 55%, 63%, and 70% of patients, respectively, when compared with an elimination rate of 5% with vitamin C as a control. Additionally, patients with vitreous hemorrhage-induced symptomatic vitreous opacities taking the mixed fruit enzyme capsules 3 times daily for 3 months reduced intraocular blood by 56% and improved visual acuity, but these effects were not found for lower doses and shorter durations when compared with a control (111650). It is unclear if these effects are due to bromelain, other ingredients, or the combination.
• Osteoarthritis. It is unclear if oral bromelain is beneficial for osteoarthritis. Details: A small clinical trial shows that taking bromelain 800 mg daily for 12 weeks as an adjunctive treatment for moderate to severe knee osteoarthritis is no more effective than placebo for improving symptom scores (18274). Other preliminary clinical research shows that taking bromelain 500 mg daily for 4 weeks for mild to moderate knee osteoarthritis is less effective than diclofenac 100 mg daily for improving quality of life, joint pain, and joint function (96216). However, preliminary clinical research shows that oral combination products containing bromelain can reduce pain and improve function in knee osteoarthritis (6252,91104,91106,92235,99467,99477,103299). Bromelain 180 mg has been used in combination with trypsin 144 mg and rutin 200 mg (Phlogenzym, Mucos Pharma GMBH; Wobenzym, Mucos Pharma GmbH) three times daily for 3-12 weeks, with effects comparable to diclofenac, usually taken as 50 mg three times daily for one week, then twice daily thereafter. This product also reduces the need for rescue analgesics by 95% when compared with placebo (6252,91104,92235,99467,99477). Other studies have used a specific combination supplement (AINAT, Laboratoire de Rhumatologie Appliquée) containing Devil's claw 600 mg, turmeric 400 mg, and bromelain 300 mg, taken 2-3 times daily for 2-8 weeks (91106) or a combination of bromelain 250 mg and papain 250 mg (Nature's Life Bromelain & Papain, NutraMarks, Inc.) twice daily, plus aceclofenac 100 mg twice daily for 6 weeks (103299).
• Pain (acute). It is unclear if oral bromelain is beneficial for acute pain. Details: A meta-analysis of 9 small clinical studies in patients experiencing acute pain due to various etiologies shows that taking bromelain slightly improves subjective pain scores and allows patients to open their mouth wider after oral operations when compared with a control (113513).
• Parturition. Although there has been interest in using oral bromelain for shortening the duration of labor, there is insufficient reliable information about the clinical effects of bromelain for this purpose.
• Periodontitis. It is unclear if oral bromelain is beneficial for periodontitis. Details: A very small clinical study in adults with periodontitis shows that taking bromelain 500 mg (Anaheal) twice daily for one week after undergoing pocket elimination surgery reduces bleeding on probing but does not improve gingival index, plaque index, or probing pocket depth when compared with placebo when assessed five weeks after surgery (111691). The validity of these effects is limited by a very small sample size and inadequate statistical power.
• Pityriasis lichenoides chronica (PLC). It is unclear if oral bromelain is beneficial for PLC. Details: A case series suggests that taking bromelain 40 mg orally three times daily for one month, then twice daily for a second month, then once daily for a third month, helps treat episodes of PLC when compared to baseline (18280).
• Postoperative pain. While evidence is mixed, some small clinical studies suggest that oral bromelain reduces postoperative pain after wisdom tooth extraction. It is unclear if bromelain improves pain after other surgical procedures. Details: Meta-analyses and clinical research in a small number of patients undergoing wisdom tooth extraction shows that bromelain modestly reduces pain for up to 8 days when compared with control (91109,91110,100750,100751). Also, three small clinical trials show that bromelain 160-1500 mg, taken in 3-4 divided doses daily for 4-6 days, reduces dental pain and swelling similarly to taking ketoprofen 100 mg twice daily, diclofenac sodium 25 mg four times daily, or aceclofenac 100 mg twice daily (91109,91110,110546). In contrast, several other small clinical studies show that taking bromelain does not reduce swelling or pain after wisdom tooth extraction when compared with placebo (91107,96214,96215). These studies might have not been sufficiently powered to detect a smaller effect. Meta-analyses also suggest that bromelain does not appear to have a significant effect on postoperative swelling or trismus (100750,100751). However, a more recent study in patients undergoing wisdom tooth extraction shows that taking bromelain 500 mg three times daily for 5 days reduces the severity of postoperative swelling and trismus when compared with aceclofenac, a nonsteroidal anti-inflammatory drug (NSAID) used in some European and Asian countries (110546). Bromelain, in combination with other ingredients, has also been evaluated for reducing pain after rotator cuff tear repair. Clinical research shows that taking a specific supplement (Tenosan, Agave) containing bromelain 50 mg, arginine-L-alpha-ketoglutarate 500 mg, methylsulfonylmethane (MSM) 550 mg, hydrolyzed collagen type I 300 mg, vitamin C 60 mg, and Vinitrox 125 mg daily for 3 months decreases shoulder pain, but does not improve shoulder function, in postoperative patients (19322).
• Postoperative swelling. Oral bromelain has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small preliminary clinical study in patients undergoing surgery of the jaw shows that taking an enzyme combination of bromelain 180 mg, rutin 200 mg, and trypsin 96 mg twice daily for 5 days in addition to standard treatment reduces soft-tissue thickness (indicating the amount of swelling) at most of the nine assessed facial points when compared to control (99476).
• Rhinosinusitis. It is unclear if oral bromelain is beneficial for rhinosinusitis. Details: Several small clinical trials show that short-term and long-term use of bromelain reduces symptoms of acute and chronic sinusitis, especially nasal mucosal inflammation and edema (18276,18277,18278,18279,91105). The trials used bromelain 40 mg orally (usually the product Ananase) four times daily for six days as an adjunct to antibiotics (18276,18278,18279) or 6 bromelain tablets each containing enzymes of 500 International Pharmaceutical Federation (FIP) units for 12 weeks (91105). Bromelain is usually taken in combination with decongestants, antihistamines, and/or antibiotics. However, the studies have a number of methodological problems, and results are inconsistent. Bromelain has also been evaluated as part of a combination product. A small study in patients over 12 years old with chronic sinusitis shows that taking a combination product containing bromelain 200 mg, Boswellia serrata, black currant, and vitamin D (Flogostop Forte, Humana Italia S.p.A) 1-2 times daily for 15-30 days as an adjunctive therapy to inhaled corticosteroids modulates hyperemia of the mucosa, rhinorrhea, and local inflammation when compared with inhaled corticosteroids alone and baseline (111501). It is unclear if these findings are due to bromelain, other ingredients, or the combination.
• Sprains. Oral bromelain has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A preliminary clinical study in patients with a sprained ankle shows that taking a specific enzyme combination (Phlogenzym, Mucos Pharma) containing bromelain 90 mg, trypsin 48 mg, and rutin 100 mg, or taking different combinations of the individual enzymes three times daily for 10 days, is no more effective for relieving pain than placebo (99473).
• Tendinopathy. Oral bromelain has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Clinical research in patients with Achilles tendon insertional tendinopathy shows that taking two sachets of a specific supplement (Tenosan, Agave, Prato, Italy) containing a total of bromelain 100 mg, arginine-L-alpha-ketoglutarate 1000 mg, methylsulfonylmethane (MSM) 1100 mg, hydrolyzed collagen type I 600 mg, vitamin C 120 mg, and Vinitrox 25 mg orally for 60 days improves function and pain when compared with placebo (19321).
• Urinary tract infections (UTIs). Oral bromelain has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical trial shows that a combination of bromelain 50 mg and trypsin 1 mg (Kimotab, Mochida Pharmaceutical), taken in a dose of 8 tablets daily for 2 days, does not improve subjective symptoms of UTIs when compared with placebo (18282).
• Venous leg ulcers. Although there has been interest in using topical bromelain for venous leg ulcers, there is insufficient reliable information about the clinical effects of bromelain for this condition.
• Wound healing. It is unclear if enzymatic debridement with bromelain improves the healing of various types of chronic wounds. Details: A meta-analysis of 12 small clinical studies shows that topical bromelain reduces time to complete debridement by around 6 days but has no effect on time to healing when compared with a control (113513). However, the validity of these effects is limited by significant publication bias and a small number of studies per outcome. One small clinical study, included in the analysis above, of patients with chronic wounds related to diabetes, surgery, trauma, or venous insufficiency shows that use of bromelain-based enzymatic debridement (EscharEx, MediWound Ltd), administered as up to ten daily applications of 4 hours each, increases the incidence of complete debridement over the next 6 months to 55% of patients, compared with only 29% of those using the bromelain-free gel. However, there was no difference in changes in wound area, non-viable tissue area, or the incidence or time to complete wound closure (108148). More evidence is needed to rate bromelain for these uses.

(Read more about BROMELAIN)

LIKELY EFFECTIVE

• Osteoarthritis. Oral glucosamine sulfate taken for at least 4 weeks is modestly beneficial for improving pain and function in knee osteoarthritis. However, oral glucosamine hydrochloride seems to only be beneficial when used in combination with chondroitin and other ingredients. It is unclear if glucosamine can slow disease progression or improve symptoms in other forms of osteoarthritis. Details: Meta-analyses of the available research in adults with KNEE osteoarthritis show that taking glucosamine SULFATE 1500 mg daily for up to 3 years modestly improves pain and function when compared with placebo (14305,89521,94382,95785,99684). Individual studies show 28% to 41% pain reduction and 21% to 46% improvement in function when compared with placebo (7026,8942,12461,20084,94382). Some research suggests that glucosamine sulfate reduces pain similarly to various non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen 400 mg three times daily and piroxicam 20 mg daily. However, NSAIDs appear to relieve symptoms within 2 weeks, while glucosamine sulfate takes 4-8 weeks. Notably, glucosamine sulfate appears to sustain benefit for longer after treatment withdrawal when compared with piroxicam (2604,20094,20096). Other clinical research shows that glucosamine sulfate 1500 mg once daily for 6 months might be more effective for reducing symptoms than acetaminophen 1 gram three times daily or 650 mg once daily in patients with moderate knee osteoarthritis (13578,20098). However, not all research shows benefit. Small clinical studies suggest that glucosamine sulfate 1500 mg daily for 2-6 months may NOT work for severe, long-standing osteoarthritis (1330,11459). It is unclear if glucosamine sulfate can slow disease progression. A specific crystalline glucosamine sulfate product (Dona, Rotta Pharmaceuticals) taken as 1500 mg daily for up to 3 years seems to prevent joint space narrowing of greater than 0.5 mm by up to 54% when compared with placebo (7026,8942,13719,42420). In contrast, other glucosamine sulfate formulations have not consistently been shown to improve symptoms or prevent joint space narrowing when compared with placebo (14305,89558,94382,95788). It is unclear if the benefit seen with this specific product (Dona) is due to bias introduced by industry funding or due to a higher quality product (42492). Glucosamine products associated with quality concerns have demonstrated inconsistent benefits in research (8128,102116). Limited research on the use of a different salt, glucosamine HYDROCHLORIDE, has found no benefit for knee osteoarthritis. A meta-analysis of clinical research and two other clinical trials show that taking glucosamine hydrochloride 1500 mg daily for up to 18 months does not seem to reduce pain when compared with placebo (18344,89519,89521). However, one small, unblinded clinical study in patients with mild to moderate osteoarthritis shows that taking a combination of glucosamine hydrochloride 480 mg every 12 hours and celecoxib 200 mg daily reduces pain scores, osteoarthritis severity, and inflammatory markers to a greater extent than celecoxib alone (106883). There is mixed evidence of benefit when glucosamine hydrochloride is used with chondroitin. Clinical research in patients over 40 years of age shows that taking a noncommercial preparation of glucosamine hydrochloride 1500 mg daily in combination with chondroitin sulfate 1200 mg daily for 6-24 months does not reduce pain when compared with placebo. The placebo response in these studies was sometimes as high as 60% (13579,14809,42477). However, a large, prospective observational study in adults with knee or hip osteoarthritis suggests that taking glucosamine hydrochloride 500 mg and chondroitin sulfate 400 mg (Theraflex, Bayer) three times daily for the first 3 weeks then twice daily thereafter for up to 64 weeks is associated with reductions in pain, stiffness, and the need for concomitant analgesic therapy and improvements in daily function and knee- or hip-related quality of life when compared to baseline. The most pronounced improvements were from 16-24 weeks (111647). The validity of these effects is limited by subjective outcomes, a lack of control group, and the observational design of the study. Furthermore, another clinical trial shows that taking a prescription product available in Spain (Droglican, Bioibérica S.A.), providing a similar daily dose of glucosamine hydrochloride with chondroitin sulfate for 6 months is non-inferior to celecoxib 200 mg daily for relieving pain, but not stiffness or function (89516). Small clinical studies show that taking a specific combination product (Cosamin or Cosamin DS, Nutramax Laboratories) containing glucosamine hydrochloride 1500-2000 mg, low molecular weight chondroitin sulfate 1200-1600 mg, and manganese ascorbate 228-304 mg, in 2-3 divided doses daily for 2-6 months improves pain in patients with mild or moderate, but not severe, osteoarthritis when compared with placebo (4237,7169). A different combination product (Gurukosamin & Kondoroichin, Suntory Wellness Ltd.) containing glucosamine hydrochloride 1200 mg, chondroitin sulfate 60 mg, and quercetin glycosides 45 mg, taken daily for 16 weeks, also seems to improve symptoms of knee osteoarthritis when compared with placebo (42514). It is unclear if the findings of any of these studies are due to glucosamine, chondroitin, other ingredients, or the combination. Despite evidence suggesting differing benefit (89521,94382), head-to-head comparisons of glucosamine sulfate and glucosamine hydrochloride are limited, and it is not universally acknowledged that these salts have different effectiveness profiles. One large clinical study in patients with knee osteoarthritis shows that taking a specific product (Artrolive, Aché Laboratórios Farmacêuticos S.A.) containing glucosamine sulfate 500 mg and chondroitin sulfate 400 mg three times daily for 4 months seems to be no different for reducing pain when compared with taking glucosamine hydrochloride 500 mg and chondroitin sulfate 400 mg (Cosamin DS, Nutramax Laboratories, Inc.) three times daily (89520). This study was funded by the supplement manufacturer. Many meta-analyses have pooled studies of both glucosamine salts together, producing largely inconsistent results (94381,99683,99685,112444). Experts have conflicting stances on the use of glucosamine. The American College of Rheumatology (ACR) strongly recommends against the use of any glucosamine products for any form of osteoarthritis (102114). Conversely, the European Society of Clinical and Economic Aspects of Osteoarthritis (ESCEO) strongly recommends the use of pharmaceutical-grade glucosamine sulfate products, such as Dona (Rotta Pharmaceuticals), in patients with osteoarthritis. Additionally, the ESCEO provides a weak recommendation against the use of glucosamine in combination with chondroitin (102141). These differing recommendations seem to be related to interpretation of the evidence for pharmaceutical-grade products. The ACR has determined that the inconsistent evidence may indicate the presence of industry bias; the ESCEO has determined that the inconsistent evidence is due to inconsistent product quality. Limited research has found mixed benefit of using glucosamine on osteoarthritis of the SPINE, HIP, or HAND. In one study of patients with osteoarthritis of the lumbar spine, taking glucosamine sulfate (Dona, Rotta Pharmaceuticals) 1500 mg daily for 6 weeks reduced pain in more patients when compared with placebo (1316). However, in another study, using a different glucosamine sulfate product (Glucosamine Sulfate, PharmaNord) 1500 mg daily for 6 months did not reduce pain when compared with placebo (89562). In patients with hip osteoarthritis, taking glucosamine sulfate 1500 mg once daily for 2 years did not reduce symptoms or slow disease progression when compared with placebo (16717,20100); however, there was a high rate of hip replacement, which may have confounded results (16717,16718). In patients with erosive osteoarthritis of the hand, observational research has found that taking glucosamine sulfate (Dona, Rotta Pharmaceuticals) 1500 mg daily along with conventional therapy for 6 months is associated with reduced hand pain, a shorter duration of morning stiffness, and improved hand function when compared with conventional therapy alone (108897). Limited research has also evaluated INTRAMUSCULAR and TOPICAL glucosamine sulfate. A clinical study in patients with mild to moderate knee osteoarthritis (radiological stage I-III) shows that giving intramuscular glucosamine sulfate 400 mg twice per week for 6 weeks reduces the severity of symptoms when compared with placebo (2605). There is also a small study showing that a topical preparation of glucosamine sulfate in combination with chondroitin sulfate, shark cartilage, and camphor reduces osteoarthritis symptoms when compared with placebo. However, any symptom relief is most likely due to the counterirritant effect of camphor and not the other ingredients (10327,12467). There is no evidence that glucosamine is absorbed topically. Glucosamine sulfate does not seem to PREVENT osteoarthritis. Clinical studies in overweight healthy females aged 50-60 years shows that taking crystalline glucosamine sulfate 1500 mg orally daily for 2.5 years does not reduce the incidence of osteoarthritis after a 6-7 year follow-up; however, it may reduce the percentage of patients who experience knee joint space narrowing (95789,97053).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Aging skin. Topical N-acetyl glucosamine has only been evaluated in combination with niacinamide for reducing hyperpigmentation and liver skin spots on aging skin; its effect when used alone is unclear. Details: A clinical study in females ages 40-60 years with skin hyperpigmentation and solar lentigines (liver spots) primarily due to aging and sun exposure shows that applying a cream containing 2% N-acetyl glucosamine and 4% niacinamide to the face twice daily with sunscreen for 10 weeks decreases facial hyperpigmentation when compared with sunscreen alone (92721). The effect of N-acetyl glucosamine alone is unclear.
• Aromatase inhibitor-induced arthralgia. Oral glucosamine sulfate has only been evaluated in combination with chondroitin; its effect when used alone is unclear. Details: A small open-label clinical study in patients with aromatase inhibitor-induced arthralgia shows that taking a combination of glucosamine sulfate 1500 mg and chondroitin sulfate 1200 mg in 2-3 divided doses daily for 24 weeks improves pain when compared to baseline in postmenopausal adults with early stage breast cancer (89561). The validity of this finding is limited by a lack of control group.
• Back pain. Although there is interest in using oral glucosamine for back pain, there is insufficient reliable information about the clinical effects of glucosamine for this condition.
• Cancer. Some low-quality observational studies have inconsistently found that glucosamine may be associated with a lower risk of different cancers; however, better quality evidence is needed. Details: A meta-analysis of observational research has found that use of glucosamine with or without chondroitin is associated with a 7% to 12% lower risk of cancer when compared with no use of glucosamine. A subgroup analysis showed a reduction in the risk of colorectal cancer, but not other types of cancer (110625). Observational research report conflicting relationships between glucosamine and cancer. Some observational research in adults in the United Kingdom has found that taking glucosamine is associated with 4% higher risk of cancer over a median follow up for 13 years. However, a subgroup analysis showed a reduction in the risk of lung cancer (110627). Other observational research in adults in the United Kingdom has found that taking glucosamine is associated with a 5% reduced risk of cancer mortality over a median follow-up of around 12 years, with reductions specifically occurring in those with kidney, lung, and rectal cancers. However, glucosamine use was not linked to a reduced risk of mortality due to bladder, brain, breast, colon, ovarian, prostate, skin, stomach, thyroid, or uterine cancer (109645). These studies are limited by observational designs, which also did not clarify the form of glucosamine used, or the dose, frequency, or duration of use. Furthermore, the adults that reported glucosamine use also reported overall healthier lifestyle habits than those that were not taking glucosamine. Although some studies attempted to control for these differences, higher quality, prospective research is needed to clarify the relationship, if any, between glucosamine and the risk for cancer and/or cancer-related mortality. Of note, some researchers have called into question the results from observational research linking glucosamine use to a lower rate of cancer, claiming that these studies suffer from a high risk of selection bias (109646).
• Cardiovascular disease (CVD). It is unclear if oral glucosamine prevents fatal or non-fatal CVD events. Details: Some observational research of adults in the United Kingdom has found that taking glucosamine is associated with an overall 15% reduced risk for fatal and non-fatal CVD events, including coronary heart disease (CHD) and stroke (99682). However, this study did not clarify the form of glucosamine used, or the dose, frequency, or duration of use. Furthermore, the adults that reported glucosamine use also reported overall healthier lifestyle habits than those that were not taking glucosamine. Conversely, an observational study in Chinese patients with osteoarthritis has found that glucosamine use is associated with a 10% increase in the risk of CVD events and a 12% increase in the risk of CHD, with no increase in the risk of stroke. The risk for these outcomes was greatest in patients with higher adherence to glucosamine and in those taking larger doses (109642). However, this study also did not clarify the form of glucosamine used or provide specifics related to the frequency or duration of use. Furthermore, glucosamine users were generally older, more likely to be on antihyperlipidemic or antiplatelet therapy, and more likely to have multiple comorbidities compared with non-users. Both studies attempted to control for the differences in characteristics between glucosamine users and non-users; despite this, higher quality, prospective research is needed to clarify the relationship, if any, between glucosamine and CVD risk.
• Colorectal adenoma. Oral glucosamine has only been evaluated in combination with chondroitin; its effect when used alone is unclear. Details: An observational study in older adults has found that taking glucosamine and chondroitin is associated with a 26% reduced risk of high-risk adenoma and 10% reduced risk of conventional adenoma when compared with not using these supplements. This benefit was not seen in a subgroup of younger females (104444). This study did not clarify the form of glucosamine used, or the dose, frequency, or duration of use.
• Colorectal cancer. It is unclear if oral glucosamine reduces the risk of colorectal cancer. Details: A large, observational study in adults has found that regular use of oral glucosamine is not associated with a reduced risk of colorectal cancer over a median of 7 years of follow-up, regardless of sex, age, body mass index, smoking status, or non-steroidal anti-inflammatory drug use (108018). This study did not clarify the form or dose of glucosamine used or the frequency or duration of use.
• Coronavirus disease 2019 (COVID-19). It is unclear if oral glucosamine is beneficial for COVID-19. Details: A large observational study in adults suggests that regular glucosamine use over a median of 1.7 years is not linked to a lower odds of COVID-19 infection but is associated with a 20% lower risk of hospital admission and a 19% lower risk of mortality due to COVID-19 when compared with adults not using glucosamine (111649). This study did not clarify the form or dose of glucosamine used or the frequency or duration of use.
• Dementia. Observational studies suggest that long-term, regular glucosamine intake might reduce the risk of developing certain types of dementia. Details: An observational study has found that regularly taking glucosamine for an average of 8.9 years is associated with a 19% lower risk of developing dementia, including Alzheimer disease and vascular dementia (110630). Another large observational study in older adults without dementia suggests that regularly taking glucosamine for a median of 12 years is associated with an 18% lower risk of vascular dementia. However, habitual glucosamine consumption is not associated with a reduced risk of Alzheimer disease or frontotemporal dementia (112461).
• Depression. It is unclear if oral glucosamine hydrochloride reduces depression symptoms. Details: A small, open-label clinical trial in patients with unipolar depression shows that taking glucosamine hydrochloride 1 gram daily for 1 week, followed by 2 grams daily for 3 weeks, reduces scores on the Hamilton Rating Scale for Depression (HAM-D) and Montgomery-Asberg Depression Rating Scale (MADRS) by 31% or 33% when compared to baseline. However, only 20% of patients experienced a 50% or greater reduction in HAM-D scores, and there were no improvements in Clinical Global Impression scores (103281). The lack of a control group limits the validity of these findings.
• Diabetes. It is unclear if oral glucosamine reduces the risk of developing type 2 diabetes in adults. Details: Observational research in adults in the United Kingdom has found that glucosamine use is associated with a 17% lower risk of type 2 diabetes. The relationship between glucosamine use and diabetes appears to be even more pronounced in patients with high baseline levels of C-reactive protein, a marker of inflammation (103234). However, this study did not clarify the form of glucosamine used, or the dose, frequency, or duration of use. Furthermore, the adults that reported glucosamine use also reported overall healthier lifestyle habits than those that were not taking glucosamine. Although this study attempted to control for these differences, higher quality, prospective research is needed to clarify the relationship, if any, between glucosamine and the risk for diabetes.
• Gout. It is unclear if oral glucosamine reduces the risk of developing gout. Details: Observational research in adults in the United Kingdom has found that glucosamine use is associated with a 19% lower risk of gout in females, but not males (109644). However, this study did not clarify the form of glucosamine used, or the dose, frequency, or duration of use. Furthermore, the adults that reported glucosamine use also reported overall healthier lifestyle habits than those that were not taking glucosamine. Although this study attempted to control for these differences, higher quality, prospective research is needed to clarify the relationship, if any, between glucosamine and the risk for gout.
• Heart failure. It is unclear if oral glucosamine prevents heart failure. Details: A large, prospective observational study in adults without heart failure suggests that taking glucosamine regularly over a median of 9 years is associated with a 13% lower risk of developing heart failure when compared with adults not taking glucosamine (111646). This study did not clarify the form or dose of glucosamine used or the frequency or duration of use.
• Hyperlipidemia. It is unclear if oral glucosamine hydrochloride improves hyperlipidemia when used with conventional medicine. Details: Preliminary clinical research shows that glucosamine hydrochloride does not reduce cholesterol or triglyceride levels in patients with hyperlipidemia. A small crossover study in older adults taking simvastatin or atorvastatin shows that adding a specific glucosamine hydrochloride product (Artrox, Pfizer) 750 mg twice daily for 4 weeks does not seem to affect lipid levels when compared with placebo (18341).
• Inflammatory bowel disease (IBD). It is unclear if oral or rectal N-acetyl glucosamine improves symptoms of IBD in children. Details: A very small clinical study in children ages 8-17 years with Crohn disease or ulcerative colitis that were unresponsive to conventional treatment suggests that oral or rectal N-acetyl glucosamine 1.5-2 grams in 10 mL water twice daily for 6 weeks might decrease symptoms of IBD when compared with baseline (10234). The validity of this finding is limited by a lack of control group.
• Interstitial cystitis. Oral glucosamine sulfate has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: An open-label clinical study in patients with interstitial cystitis shows that taking a specific product (CystoProtek, Tischon Corporation) containing glucosamine sulfate 120 mg, sodium hyaluronate 10 mg, chondroitin sulfate 150 mg, quercetin 150 mg, and rutin 20 mg per capsule, as two capsules twice daily for 12 months, reduces symptom severity by up to 52% when compared with baseline (42391). The validity of this finding is limited by a lack of control group.
• Joint pain. Oral glucosamine has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical study in patients with joint pain shows that taking capsules of a specific combination product (Instaflex Joint Support, Direct Digital) containing glucosamine sulfate 1500 mg, methylsulfonylmethane 500 mg, white willow bark extract 250 mg, ginger root concentrate 50 mg, Boswellia serrata extract 125 mg, turmeric root extract 50 mg, cayenne 40 m H.U. 50 mg, and hyaluronic acid 4 mg, daily in three divided doses for 8 weeks, reduces joint pain severity by 37% compared to only 16% with placebo. However, the specific combination product does not appear to improve joint stiffness or function compared with placebo (89560).
• Kashin-Beck Disease. It is unclear if oral glucosamine hydrochloride improves Kashin-Beck Disease symptoms such as pain. Details: A small clinical study in Chinese adults with Kashin-Beck Disease shows that taking glucosamine hydrochloride 480 mg three times daily along with chondroitin sulfate 600 mg twice daily for 6 months decreases pain scores by at least 20% to 50% in more patients when compared with placebo. Taking glucosamine alone had a non-significant trend toward pain reduction in these patients (42516). An open-label study in Chinese adults with Kashin-Beck Disease shows that taking glucosamine hydrochloride 750 mg twice daily for 6 weeks seems to be no different for improving pain and physical function when compared with taking to diclofenac 50 mg twice daily or naproxen 300 mg twice daily (18339). The validity of this finding is limited by a lack of blinding.
• Kidney stones (nephrolithiasis). Oral glucosamine might reduce the risk of developing kidney stones. Details: A large observational study in adults without kidney stones suggests that regularly taking glucosamine is associated with a 28% lower risk of new-onset kidney stones in people with a total sedentary time under 3.5 hours daily. This association follows a dose-dependent relationship. However, regular glucosamine use does not seem to reduce the risk of new-onset kidney stones in people with total sedentary time exceeding 3.5 hours daily (112451).
• Knee pain. Small clinical studies suggest that oral glucosamine hydrochloride might improve exercise-induced knee pain and chronic knee pain. However, it is unclear if glucosamine sulfate, N-acetyl glucosamine, or lower doses of glucosamine hydrochloride are beneficial in these patients. Details: A small clinical study in athletes following an acute knee injury shows that taking glucosamine sulfate 500 mg three times daily for 28 days does not improve pain but might modestly improve mobility when compared with placebo (20103). Glucosamine has also been evaluated for chronic knee pain. A small clinical study in patients with chronic knee pain of unclear origin shows that taking glucosamine hydrochloride 2000 mg daily for 12 weeks might modestly improve pain when compared with placebo (10312). However, lower doses of glucosamine hydrochloride and N-acetyl glucosamine used in combination with other ingredients have not demonstrated benefit for chronic knee pain. A small clinical trial in Japanese adults over 40 with knee pain shows that taking a combination supplement with glucosamine hydrochloride and other ingredients for 16 weeks does not improve pain, function, or walking speed when compared with placebo. The combination supplement provided glucosamine hydrochloride 1200 mg, chondroitin sulfate 60 mg, type II collagen peptides 45 mg, quercetin glycosides 90 mg, imidazole peptides 10 mg, and vitamin D 200 IU daily (95784). Another small clinical study in Japanese patients over 50 years of age with chronic knee pain shows that taking a specific supplement (Walker's Glucosamine, Kyowa) containing N-acetyl glucosamine 100 mg and chondroitin sulfate 180 mg daily for 24 weeks does not reduce pain or improve knee function when compared with placebo (95795).
• Multiple sclerosis (MS). It is unclear if oral glucosamine sulfate is beneficial in patients with MS. Details: A small clinical study in patients with MS shows that taking glucosamine sulfate 1000 mg once daily for 6 months modestly reduces relapse when compared to baseline, but not when compared with placebo (20104).
• Overall mortality. It is unclear if oral glucosamine reduces overall mortality. Details: An observational study in the United States has found that regular use of oral glucosamine, with or without chondroitin, for an average of 8 years is associated with a 30% lower risk of mortality when compared with no glucosamine use. However, when adjusted for covariates such as age, body-mass index, and comorbidities, there was no difference in overall mortality (110626). In contrast, a cross-sectional observational study has found that using oral glucosamine and chondroitin for at least one year is associated with 27% reduced incidence of overall mortality and 58% reduced incidence of cardiovascular mortality when compared with not using these supplements (104445). This study did not clarify the form of glucosamine used, or the dose, frequency, or duration of use. Furthermore, the adults that reported glucosamine and chondroitin use also reported overall healthier lifestyle habits than those that were not taking glucosamine and chondroitin. Although this study attempted to control for these differences, higher quality, prospective research is needed to clarify the relationship, if any, with overall mortality. Of note, some researchers have called into question the results from observational research linking glucosamine use to a lower rate of overall mortality, claiming that these studies suffer from a high risk of selection bias (109646).
• Postoperative recovery. It is unclear if oral glucosamine sulfate improves recovery after surgery. Details: A small clinical study in male athletes who have undergone anterior cruciate ligament (ACL) reconstruction shows that taking glucosamine sulfate (Solgar Inc.) 1000 mg daily for 8 weeks does not improve rehabilitation outcomes such as functional ability, pain, and muscular performance when compared with placebo (95584).
• Rheumatoid arthritis (RA). It is unclear if oral glucosamine hydrochloride is beneficial in patients with RA. Details: A small clinical study in patients with RA shows that taking glucosamine hydrochloride tablets (Rohto Pharmaceutical Co.) 500 mg three times daily by mouth for 12 weeks reduces pain, but not the number of painful or swollen joints, when compared with placebo (17407).
• Stroke. It is unclear if oral glucosamine is beneficial for reducing stroke risk. Details: An observational cohort study of adults in the United Kingdom found that taking glucosamine is associated with a modest 9% reduced risk for overall stroke; however, sub-analyses show that glucosamine use is not associated with a reduced risk for fatal or non-fatal stroke, hemorrhagic stroke, or ischemic stroke (99682). This study did not clarify the form of glucosamine used, or the dose, frequency, or duration of use. Furthermore, the adults that reported glucosamine use also reported overall healthier lifestyle habits than those that were not taking glucosamine. A case-control study in Spanish patients found that glucosamine use is associated with 45% lower odds of ischemic stroke when compared with non-use; however, the benefit was only observed in patients taking glucosamine for 1 year or less (109643). This study did not clarify the form of glucosamine used or the dose or frequency of use. Furthermore, patients in the control group were generally healthier and less likely to have a history of cardiovascular disease, diabetes, or hyperlipidemia. Although both studies attempted to control for differences between patient populations, higher quality, prospective research is needed to clarify the relationship, if any, between glucosamine and stroke risk.
• Temporomandibular disorders (TMD). It is unclear if oral glucosamine sulfate is beneficial in patients with temporomandibular joint osteoarthritis. Details: A small and low-quality clinical study in patients with temporomandibular joint osteoarthritis shows that taking glucosamine sulfate 500 mg three times daily for 90 days seems to be no different than taking ibuprofen 400 mg three times daily for relieving pain and improving functional abilities such as chewing, yawning, talking, and laughing (3714). However, another small clinical study in patients with the same condition shows that taking glucosamine sulfate 1200 mg daily for 6 weeks does not improve pain or jaw opening capacity when compared with placebo (20105). Glucosamine sulfate has also been evaluated in combination with chondroitin for this condition. A meta-analysis of two small clinical studies in patients with TMD shows that taking glucosamine sulfate 1500 mg and chondroitin sulfate 1200 mg daily for 2 months does not reduce pain or increase maximum mouth opening when compared with tramadol 50-100 mg daily (109647). Another small clinical trial in children aged 10-13 years with class II malocclusion shows that application of a specific combination gel product containing glucosamine, chondroitin, and essential oils (Jointace Gel, Vitabiotics) with an expander device, twice daily for 3 months does not improve temporomandibular space measures or pain or tension scores, when compared with placebo (110629).
• Wound healing. Although there is interest in using topical glucosamine for wound healing, there is insufficient reliable information about the clinical effects of glucosamine for this condition. More evidence is needed to rate glucosamine for these uses.

(Read more about GLUCOSAMINE)

LIKELY INEFFECTIVE

• Cancer. Most clinical research shows that oral shark cartilage is not beneficial in people with advanced cancer. Details: Most clinical research shows that taking shark cartilage orally offers no benefit in people with advanced, previously-treated cancer, including breast, colorectal, lung, prostate, and brain cancers, and non-Hodgkin's lymphoma (2015,6716,6717,13086,17102,74731). These studies used shark cartilage powder (Cartilade, Cartilage USA; Benefin, Lane Labs) at doses of 1-1.3 grams/kg daily or 96 grams daily (2015,6717,13086) and shark cartilage extract (AE-941, Neovastat) (17102). Studies of shark cartilage in less advanced cancer have not been published.

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Age-related macular degeneration (AMD). Although there is interest in using oral shark cartilage for AMD, there is insufficient reliable information about the clinical effects of shark cartilage for this condition.
• Diabetic retinopathy. Although there is interest in using oral shark cartilage for diabetic retinopathy, there is insufficient reliable information about the clinical effects of shark cartilage for this condition.
• Kaposi sarcoma. It is unclear if oral shark cartilage is beneficial in patients with Kaposi sarcoma. Details: There is anecdotal evidence that taking shark cartilage orally, 3.75-4.5 grams daily divided into 3 doses, might decrease cutaneous Kaposi sarcoma lesions and increase histological regression (4938). Prospective clinical research is needed to confirm this finding.
• Osteoarthritis. Topical shark cartilage has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research shows that applying a topical preparation of shark cartilage 140 mg, chondroitin sulfate 50 mg, glucosamine sulfate 30 mg, and camphor 32 mg per gram, as needed for up to 8 weeks, reduces osteoarthritis symptoms. However, any symptom relief is most likely due to the counterirritant effect of camphor and not the other ingredients (10327).
• Psoriasis. It is unclear if topical shark cartilage is beneficial in patients with psoriasis. Details: Preliminary clinical research in adults with plaque psoriasis shows that applying a specific solution of a shark cartilage extract (AE-941, Neovastat) topically, 30-240 mL to affected areas daily for up to 12 weeks, can improve the appearance of plaques and reduce itching when compared with baseline (4893,10399).
• Renal cell carcinoma. It is unclear if oral shark cartilage is beneficial in patients with renal cell carcinoma. Details: Preliminary clinical research shows that taking a specific solution of shark cartilage extract (AE-941, Neovastat), 60-240 mL daily orally, seems to increase survival in patients with advanced renal cell carcinoma (4894,10900). However, no further clinical evidence has been published, and this specific extract is no longer being evaluated for the treatment of renal cell carcinoma.
• Rheumatoid arthritis (RA). Although there is interest in using oral shark cartilage for RA, there is insufficient reliable information about the clinical effects of shark cartilage for this condition. More evidence is needed to rate shark cartilage for these uses.

(Read more about SHARK CARTILAGE)

LIKELY SAFE ...when used orally and appropriately in amounts commonly found in foods. Bilberry has Generally Recognized As Safe status (GRAS) for use in foods in the US (4912).

POSSIBLY SAFE ...when used orally and appropriately for medicinal purposes. Bilberry fruit extracts have been used with apparent safety in clinical trials at a dose of up to 160 mg daily for up to 6 months (39,40,8139,9739,14280,35472,35510,35512,103190,104192,104195). A higher bilberry extract dose of 1.4 grams daily has been used with apparent safety for up to 4 weeks (104194). Whole bilberries or bilberry juice have also been consumed with apparent safety in quantities of 100-160 grams daily for up to 35 days (35463,91506).

POSSIBLY UNSAFE ...when the leaves are used orally in high doses or for a prolonged period. Death can occur with chronic use of 1.5 gram/kg daily (2).

PREGNANCY AND LACTATION: LIKELY SAFE
when used orally in the amounts commonly found in foods. However, there is insufficient reliable information available about the safety of bilberry when used in medicinal amounts during pregnancy and lactation; avoid using.

(Read more about BILBERRY)

POSSIBLY SAFE ...when used orally, topically, subcutaneously, or intramuscularly and appropriately. Bovine cartilage has been used orally, topically, subcutaneously, and intramuscularly for up to five years without significant adverse effects (2009,2010,36960,92771). Orally, up to 9 grams daily has been used without evidence of toxicity (2010). Subcutaneously, up to 40 grams weekly and 300 grams total have been injected without evidence of toxicity (2009). Intramuscularly, a complex including bovine cartilage and bone marrow (Rumalon, Robapharm) has been used safely when given in a total of ten treatment courses over five years (92771). However, since these preparations are derived from animals, there is concern about contamination with diseased animal parts (see Adverse Reactions) (1825). So far, there are no reports of disease transmission to humans due to use of contaminated bovine cartilage.

PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using.

(Read more about BOVINE CARTILAGE)

POSSIBLY SAFE ...when used orally and appropriately. Doses up to 240 mg daily have been used safely for up to a year (6252,6253,10622,11457,18281,18284,91104,91105,91106,91111)(96449,103298). Higher doses up to 3200 mg daily have been used safely, short-term (18283,110546). ...when used topically and appropriately. Bromelain has been used safely as a debriding agent for up to 4 hours (18275,91113,103297,108148,108149).

PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using.

(Read more about BROMELAIN)

LIKELY SAFE ...when glucosamine sulfate is used orally and appropriately. Glucosamine sulfate has been used safely in multiple clinical trials at a dose of 1000-1500 mg daily for 4 weeks to 3 years (2604,7026,8942,11340,12461)(14305,16717,89558,89567,94380,94382,95785).

POSSIBLY SAFE ...when glucosamine hydrochloride is used orally and appropriately. Glucosamine hydrochloride has been used with apparent safety at a dose of 1400-1600 mg daily for up to 2 years (4237,13579,14809,18344,42477,89516,89519,95784). Glucosamine hydrochloride 2 grams daily has also been used with apparent safety for up to 3 weeks (103281). ...when N-acetyl glucosamine is used orally and appropriately. N-acetyl glucosamine 100 mg daily has been used with apparent safety for up to 24 weeks (95795). ...when N-acetyl glucosamine is applied topically and appropriately. A 2% N-acetyl glucosamine cream has been safely used for up to 10 weeks (92721). ...when N-acetyl glucosamine is used rectally and appropriately. N-acetyl glucosamine 3-4 grams daily in 2 divided doses has been safely used (10234). ...when glucosamine sulfate is used intramuscularly and appropriately, short-term. Intramuscular glucosamine sulfate seems to be well tolerated when given twice weekly for up to 6 weeks (2605).

PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using.

(Read more about GLUCOSAMINE)

POSSIBLY SAFE ...when used orally and appropriately, short-term. Shark cartilage has been used with apparent safety in clinical trials lasting up to 24 weeks (2015,4893,4938,6709,6716,6717,13086,74741) and for up to 40 months in patients with advanced cancer (10900,17102). ...when used topically and appropriately, short-term. Shark cartilage appears to be safe when applied topically for up to 8 weeks (74729).

PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using.

(Read more about SHARK CARTILAGE)

ANTICOAGULANT/ANTIPLATELET DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, bilberry fruit extract might increase the risk of bleeding when taken with anticoagulant or antiplatelet drugs.  Details In vitro, animal, and clinical research suggest that anthocyanidin extracts from bilberry can inhibit platelet aggregation (16631,35455,35503,35504,35505).

ANTIDIABETES DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, bilberry leaf or fruit extract may increase the risk of hypoglycemia when taken with antidiabetes drugs.  Details Animal research suggests that bilberry leaf extract might have blood glucose-lowering activity (1264). Also, one small clinical trial in patients with type 2 diabetes shows that taking bilberry fruit extract 470 mg as a single dose prior to an oral glucose tolerance test lowers plasma glucose levels when compared with placebo (91507).

CYTOCHROME P450 2E1 (CYP2E1) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, bilberry fruit extract might decrease levels of drugs metabolized by CYP2E1.  Details Animal research shows that exposure to small concentrations of bilberry extract in drinking water for around one month increased CYP2E1 activity by 31%. However, exposure over a 2-month period did not increase CYP2E1 activity (103191). This effect has not been reported in humans.

ERLOTINIB (Tarceva) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, bilberry fruit extract might reduce the efficacy of erlotinib.  Details In vitro research suggests that bilberry fruit extract and its constituents, delphinidin and delphinidin-3-O-glucoside, inhibit the activity of erlotinib (97031). This interaction has not been reported in humans.

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ANTICOAGULANT/ANTIPLATELET DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Bromelain may have antiplatelet effects and may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.  Details There is one case report of a patient experiencing minor bruising while taking bromelain with naproxen (14806). Bromelain is thought to have antiplatelet activity (10639,14806,18285,18286,37234). Whether this interaction is of concern with topical bromelain is unclear. Interference with coagulation of burn wounds has been reported in a patient receiving bromelain-based enzymatic debridement. However, observational research has found that topical bromelain debridement is not associated with increases or decreases in laboratory markers of coagulation when compared with surgical debridement (110547).

TETRACYCLINE ANTIBIOTICS Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = B Theoretically, bromelain might increase levels of tetracycline antibiotics.  Details Laboratory research suggests that bromelain might increase the absorption of tetracycline antibiotics. However, a study in healthy adults reported no difference in tetracycline plasma levels when a 500 mg dose was taken with or without bromelain 80 mg (14296).

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ACETAMINOPHEN (Tylenol, others) Interaction Rating = Minor Be watchful with this combination. Severity = Insignificant •  Occurrence = Possible •  Level of Evidence = B Acetaminophen might interfere with the activity of glucosamine sulfate by interacting with the sulfate portion.  Details Anecdotal reports suggest that adding glucosamine to an acetaminophen regimen might decrease pain control in patients with osteoarthritis (14806). Some research suggests that the sulfate portion of glucosamine sulfate might contribute to its effect in osteoarthritis. Since acetaminophen metabolism requires sulfur and reduces serum sulfate concentrations, acetaminophen could theoretically interfere with the action of glucosamine sulfate. Conversely, the administration of sulfate could theoretically decrease the effectiveness of acetaminophen in sulfate-deficient people by increasing its clearance (10313).

ANTIDIABETES DRUGS Interaction Rating = Minor Be watchful with this combination. Severity = Moderate •  Occurrence = Unlikely •  Level of Evidence = B Despite initial concerns, it is unlikely that glucosamine will interfere with the effects of antidiabetes drugs.  Details In vitro and animal research has suggested that glucosamine might increase insulin resistance or decrease insulin production (371,372,3406,18342,18343). This has raised concerns that taking glucosamine might worsen diabetes and decrease the effectiveness of diabetes drugs. However, clinical research suggests that glucosamine does not have adverse effects on blood glucose or glycated hemoglobin (HbA1C) in healthy, obese, or type 2 diabetes patients (7026,7075,8942,10311,10317,15111).

TOPOISOMERASE II INHIBITORS Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically glucosamine may induce resistance to topoisomerase II inhibitors.  Details In vitro research suggests that glucosamine might induce resistance to etoposide (VP16, VePesid) and doxorubicin (Adriamycin) by reducing inhibition of topoisomerase II, an enzyme required for DNA replication in tumor cells (7639). This effect has not been reported in humans.

WARFARIN (Coumadin) Interaction Rating = Major Do not take this combination. Severity = High •  Occurrence = Probable •  Level of Evidence = D Glucosamine might increase the anticoagulant effects of warfarin and increase the risk of bruising and bleeding.  Details In two individual case reports, glucosamine/chondroitin combinations were associated with a significant increase in international normalized ratio (INR) in patients previously stabilized on warfarin (11389,16130). In one case, the increase in INR occurred only after tripling the dose of a glucosamine/chondroitin supplement from 500 mg/400 mg daily to 1500/1200 mg daily (16130). Additionally, 20 voluntary case reports to the U.S. Food & Drug Administration (FDA) have linked glucosamine plus chondroitin with increased INR, bruising, and bleeding in patients who were also taking warfarin (16130). There have also been 20 additional case reports to the World Health Organization (WHO) that link glucosamine alone to increased INR in patients taking warfarin (16131). The mechanism of this interaction is unclear. Glucosamine is a small component of heparin, but is not thought to have anticoagulant activity; however, animal research suggests that it might have antiplatelet activity (16131).

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IMMUNOSUPPRESSANTS Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, shark cartilage might interfere with immunosuppressive therapy.  Details In vitro evidence suggests that shark cartilage might stimulate immune responses (74692,74700,93050). This effect has not been reported in humans.

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General ...Orally, bilberry fruit, juice, and extracts seem to be well tolerated.
Most Common Adverse Effects:
Orally: Dark-colored stools, flatulence, and gastrointestinal discomfort.

Gastrointestinal ...In one small clinical trial, mild-to-moderate flatulence was reported in 33% of patients taking sieved bilberries and concentrated bilberry juice (91506). However, the patients in this study had ulcerative colitis, and the study lacked a control group, limiting the validity of this finding. In another small clinical study of males with age-related cognitive impairment, temporary adverse gastrointestinal (GI) effects were reported in 13% of patients drinking a combination of bilberry and grape juice. However, the adverse GI effect rate was identical in patients drinking a placebo juice (110641). A post-marketing surveillance report of 2295 patients using bilberry extract (Tegens) found that 1% of patients complained of GI discomfort and less than 1% experienced nausea or heartburn (35500).
Theoretically, fresh bilberry fruit may have laxative effects. One clinical trial noted an increased frequency of bowel movements following the administration of a combination formulation containing aerial agrimony parts, cinnamon quills, powdered bilberry fruit, and slippery elm bark (35462). It is unclear if these effects were due to bilberry, other ingredients, or the combination.

Other ...Orally, bilberry may cause discoloration of feces and the tongue. In one study, a dark-bluish to black discoloration of both the feces and the tongue was observed following consumption of sieved bilberries and concentrated bilberry juice. In one patient, a slight discoloration of the teeth has also been observed (91506). In another study, 50% of patients reported dark green stools after taking bilberry extract 700 mg twice daily for 4 weeks (104194).

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General ...Orally, subcutaneously, and intramuscularly, bovine cartilage seems to be well tolerated.
Most Common Adverse Effects:
Orally: Fatigue, gastrointestinal upset, and osmotic diarrhea.
Injected: When administered subcutaneously or intramuscularly, bovine cartilage might initially cause a local allergic reaction, manifesting as local redness, swelling, and itching.
Serious Adverse Effects (Rare):
Injected: Nephrotic syndrome.

Gastrointestinal ...Orally, bovine cartilage can cause gastrointestinal upset and osmotic diarrhea (2009).

Genitourinary ...Orally, bovine cartilage can cause scrotal edema (2009).

Immunologic ...Local allergic reactions, manifesting as local redness, swelling, and itching, have been reported in patients receiving intramuscular or subcutaneous injections of bovine cartilage (2010,92771). However, rates of these adverse events in one study were similar to placebo (92771).

Neurologic/CNS ...Orally, bovine cartilage can cause fatigue (2009).

Renal ...When injected, cases of nephrotic syndrome have been reported with a preparation containing bovine cartilage and an extract of bovine marrow (36967,36966,36968).

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General ...Orally, bromelain seems to be well tolerated.
Most Common Adverse Effects:
Orally: Diarrhea, flatulence, gastric upset, headache.
Topically: Pruritus, urticaria.

Dermatologic ...Topically, bromelain may cause dermal allergic reactions including urticaria, pruritus, and skin swelling (9184). Redness, swelling, burning, pain at the application site, and cellulitis have also been reported rarely (108148,113513). In one case, a fixed drug eruption with pruritis near the groin was reported in a 33-year-old male taking bromelain 50 mg orally daily for 10 days. After discontinuation of bromelain and treatment with topical corticosteroid, the lesion resolved. Upon re-challenge with bromelain, the lesion reappeared in the same area (103300).
In another case report, a 61-year-old male with a history of chronic lower leg ulceration secondary to chronic venous hypertension and recurrent deep vein thrombosis on rivaroxaban presented with a deep-dermal burn on his lower calf. Bromelain-based topical enzymatic debridement agent Nexobrid 2 grams was applied to the burn site. Thirty minutes later, the patient experienced two instances of hemorrhage at the site of debridement. The patient was stabilized and treated with fluids, packed red cells, and tranexamic acid, and then the Nexobrid was removed (111656). Caution should be used in patients with underlying coagulopathies.

Gastrointestinal ...Orally, bromelain may cause gastrointestinal disturbances, including diarrhea, nausea, vomiting, flatulence, and abdominal pain (9184,18274,18282,96216,113513).

Immunologic ...Immunoglobulin E (IgE)-mediated allergic reactions to bromelain may occur (9184).
If inhaled, bromelain may cause sensitization and allergic reactions such as asthma (37199,37215,37233). In case reports of occupational inhalation of bromelain, additional allergic symptoms included difficulty swallowing, throat itching, eye irritation, and rhinitis (37214).

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General ...Orally, all forms of glucosamine seem to be well tolerated. Topically and rectally, N-acetyl glucosamine also seems to be well tolerated. Intramuscularly, glucosamine sulfate seems to be well tolerated. However, a thorough evaluation of safety outcomes has not been conducted for non-oral routes of administration.
Most Common Adverse Effects:
Orally: Bloating, constipation, cramps, diarrhea, heartburn, nausea.
Serious Adverse Effects (Rare):
Orally: There have been rare reports of severe allergic reactions and hepatotoxicity.

Cardiovascular ...One case of mesenteric occlusion in a clinical trial was considered possibly related to use of oral glucosamine hydrochloride and chondroitin sulfate (89520).
Some observational research has found that glucosamine use in patients with osteoarthritis is associated with a higher risk of cardiovascular disease (CVD) events when compared with non-use (109642). However, glucosamine users tended to be older, have multiple comorbidities, and be on antihyperlipidemic or antiplatelet therapy. Furthermore, other observational research in healthy adults has found that glucosamine use is associated with a reduced risk of fatal and non-fatal CVD events (99682). Higher quality, prospective research is needed to clarify the relationship, if any, between glucosamine and CVD risk.

Dermatologic ...Orally, glucosamine might cause skin reactions, including itching, rash, and erythema (2608,20084,89567,110628). Also, fingernail and toenail toughening, with an increased rate of growth, has been reported (89572). Topically, N-acetyl glucosamine 2% with niacinamide 4% cream might cause rare skin reactions (92721). Photosensitization that was reproducible with re-challenge was reported in a case report of an individual using glucosamine (form unknown) and chondroitin (10408).

Endocrine ...Orally, glucosamine does not seem to impact blood glucose. Preliminary research and anecdotal reports have found that various forms of glucosamine might increase insulin resistance or decrease insulin production, increasing fasting plasma glucose levels (22,371,372,1203,3406,5059,7637,14810). This has raised concerns that taking glucosamine sulfate might worsen diabetes and decrease the effectiveness of diabetes drugs. However, clinical research suggests that various forms of glucosamine do not have adverse effects on blood glucose or glycated hemoglobin (HbA1C) in healthy, obese, patients with type 2 diabetes or impaired glucose tolerance (7026,7075,7638,8942,10311,10317,12107,14808,15111,89563).

Gastrointestinal ...Orally, glucosamine has been associated with gastrointestinal problems, including epigastric and abdominal pain, cramps, heartburn, diarrhea, nausea, dyspepsia, vomiting, constipation, and flatulence (1520,2608,16717,20084,20104,20105,89561,89562,89567,89568)(108897,110628,111647). In older persons, use of glucosamine sulfate is associated with oral dryness (89564). In a clinical trial, a case of Helicobacter pylori gastritis was considered probably related to the use of glucosamine hydrochloride (89516).

Hepatic ...Although relatively uncommon, combinations of glucosamine and chondroitin sulfate have been associated with acute liver injury that mimics autoimmune hepatitis. Of 151 patients at an outpatient clinic for liver diseases, 23 acknowledged use of products containing glucosamine (form unspecified) and/or chondroitin. However, only 2 cases had an apparent relationship between transaminase elevation and the use of recommended doses of glucosamine and chondroitin sulfate. Aminotransferase levels, which were increased by four- to seven-fold, returned to normal following discontinuation of treatment (89515). In another case, a 65-year-old male presented to the hospital with signs and symptoms of drug-induced autoimmune hepatitis. The patient had used Condrosulf, containing chondroitin sulfate, for two years, followed by Vita Mobility Complex, containing chondroitin sulfate and glucosamine sulfate, for 8 weeks. The patient required maintenance treatment with azathioprine to remain in remission (89518). A case of acute cholestatic hepatitis due to Glucosamine Forte, which contains glucosamine hydrochloride, chondroitin sulfate, Devil's claw, and shark cartilage, has been reported (89522). It is unclear whether these adverse events were related to glucosamine, other ingredients, or the combination.

Immunologic ...There is some concern that glucosamine products might cause allergic reactions in sensitive individuals. One review of glucosamine-related adverse events in Australia found that 72% of all reports involved hypersensitivity reactions. Of these reactions, 35% were mild, including pruritis, urticaria, and lip edema, 49% were moderate, including dyspnea, and 16% were severe, including gait disturbance, somnolence, and hypotension. Anaphylaxis was reported in 1.5% of cases (102115). Also, in one clinical trial, a single patient developed allergic dermatitis considered to be likely due to glucosamine hydrochloride (89516). Glucosamine is derived from the exoskeletons of shrimp, lobster, and crabs. However, it is unclear if these adverse reactions were due to a shellfish sensitivity or general atopy. Additionally, shellfish allergies are caused by IgE antibodies to antigens in the meat of shellfish, not to antigens in the exoskeleton. Regardless, it is possible that some glucosamine products might be contaminated by this allergen during production (102115).

Neurologic/CNS ...Orally, glucosamine has been reported to cause drowsiness and headache (2608,89561). Glucosamine plus chondroitin combination products that also contain manganese (e.g., CosaminDS) should always be taken according to product directions. When taken at doses slightly higher than the recommended dose, these products can sometimes supply greater than the tolerable upper limit (UL) for manganese which is 11 mg/day. Ingestion of more than 11 mg/day of manganese might cause significant central nervous system toxicity (7135).

Ocular/Otic ...In older persons, use of glucosamine sulfate has been associated with ocular dryness (89564). Increased intraocular pressure has occurred with glucosamine sulfate supplementation (89573,112460). Data from the FDA MedWatch adverse event reporting system shows that 0.21% of subjects taking glucosamine reported glaucoma, which is significantly greater than the 0.08% of subjects who reported glaucoma while using any other drug (112460).

Pulmonary/Respiratory ...Cases of asthma exacerbations associated with the use of glucosamine (form unknown)-chondroitin products have been reported (10002).

Renal ...Anecdotal reports have associated glucosamine with nephrotoxicity signals such as modestly elevated creatine phosphokinase and 1+ to 2+ proteinuria, but changes in kidney function have not been reported in long-term studies (7026,8942,10408,10409). It was also noted that effects may have been due to other concurrent medications or impurities in glucosamine-chondroitin products. Cases of acute interstitial nephritis induced by glucosamine (form unknown) have also been reported (89523).

Other ...There has been concern that glucosamine might increase the risk of metabolic disturbances resulting in increased cholesterol levels and blood pressure. However, glucosamine does not appear to increase the risk of these adverse effects. Taking glucosamine sulfate for up to 3 years does not significantly increase blood glucose or lipid levels, or cause any other disturbances in metabolism (7026,7075,8942,10311,10317).

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General ...Orally, shark cartilage is generally well tolerated.
Most Common Adverse Effects:
Orally: Constipation, dizziness, dyspepsia, erythema, fatigue, hypotension, nausea, taste disturbance, and vomiting.
Serious Adverse Effects (Rare):
Orally: Altered consciousness, decreased motor strength, decreased sensation, generalized weakness, hepatitis, hyperglycemia, hypoglycemia, and peripheral edema.

Cardiovascular ...Orally, shark cartilage can cause hypotension and peripheral edema (2014,2015,6716,10900).

Endocrine ...Orally, shark cartilage can cause hyperglycemia, hypoglycemia, and hypercalcemia (2014,2015,6716,10900,74724).

Gastrointestinal ...Orally, shark cartilage can cause taste disturbances, nausea, vomiting, dyspepsia, constipation, cramping, and bloating (2014,2015,6716,10900,74724,74730,74731).

Hepatic ...Orally, shark cartilage can cause acute hepatitis, with symptoms including low-grade fever, jaundice, yellowing of the eyes, right upper quadrant tenderness, and elevated liver enzymes (2012).

Musculoskeletal ...Orally, shark cartilage can cause decreased motor strength, generalized weakness, and decreased performance (2014,2015,6716,10900).

Neurologic/CNS ...Orally, shark cartilage can cause dizziness, altered consciousness, decreased sensation, and fatigue (2014,2015,6716,10900,74725).

(Read more about SHARK CARTILAGE)