Are There Side Effects of Glucosamine Chondroitin or Interaction With Meds?

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Taking supplements with a combination of glucosamine and chondroitin seems to help reduce osteoarthritis pain, reports the American Academy of Orthopaedic Surgeons. Both substances have anti-inflammatory effects that may be beneficial for this condition. Side effects are uncommon. Consult a qualified health care provider before you take glucosamine-chondroitin supplements to learn how to prevent negative effects and to rule out potential interactions with medication.

Gastrointestinal Effects

Glucosamine chondroitin supplements can cause gastrointestinal side effects, which may include nausea, diarrhea, constipation, heartburn and pain in the middle upper abdomen, similar to the pain of acid reflux.

Serious Side Effects

Side effects that could indicate heart, circulatory system problems or fluid retention call for medical attention. Glucosamine-chondroitin supplements have been connected with swollen ankles and feet, heart palpitations and other heartbeat irregularities.

Allergic Reaction

Because glucosamine is made from the shells of crustaceans such as crabs, lobsters and shrimp, you could have an allergic reaction to glucosamine if you have a shellfish allergy. This is only theoretical, as people with shellfish allergies generally are allergic to proteins in the meat rather than to the shells. Nevertheless, seek immediate medical attention if you develop symptoms such as a rash, hives, itching, wheezing, difficulty breathing, or swelling of the mouth, throat or eyelids.

Interactions with Blood Thinners

Theoretically, chondroitin could increase the effects of blood-thinning medications because it is similar to heparin, a drug used for this purpose, according to the University of Maryland Medical Center. Warfarin is another medicine prescribed as a blood thinner, and antiplatelet medicines also have this effect. Although the risk of an interaction is likely very small with less potent substances, you should be cautious about taking aspirin, ibuprofen, fish oil and vitamin E when you use glucosamine-chondroitin supplements. Watch for any unusual bruising or bleeding while you're taking glucosamine-chondroitin.

Cancer Treatment Interactions

Glucosamine could decrease the effectiveness of certain medications used for treating cancer, according to MedlinePlus, a website affiliated with the U.S. National Institutes of Health. Check with your doctor if you are undergoing cancer treatments to make sure that this is not the case with any drugs you are on.