Some clinical studies have shown that glucosamine sulfate is comparable to the nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen for relief of joint discomfort. Although NSAIDs medications can have a faster pain-relieving effect, there are potential side effects of those medications. Other clinical research shows that glucosamine sulfate at a dose of 1500 mg once daily for 6 months might be more effective than acetaminophen 1 gram 3 times daily for reducing symptoms in patients with moderate joint discomfort of the knee.

The available evidence from these studies suggests that glucosamine sulfate may be effective and safe in delaying the progression and improving the symptoms of knee pain, stiffness, and dysfunction.

WARNINGS: Taking glucosamine alone or in combination with chondroitin might increase the anticoagulant effects of warfarin (Coumadin) and increase the risk of bruising and bleeding. Patients taking warfarin should be advised to avoid or
use glucosamine cautiously.

CAUTION: There is concern that glucosamine products might cause allergic reactions in people who are sensitive to shellfish. Glucosamine is derived from the exoskeletons of shrimp, lobster, and crabs. But allergic reactions in people
with shellfish allergy are caused by IgE antibodies to antigens in the meat of shellfish, and usually not to antigens in the shell. There are no documented reports of allergic reaction to glucosamine in shellfish allergic patients. There is also some evidence that patients with shellfish allergy can safely take glucosamine products.