Chondroitin Sulfate Side Effects and Warnings

Chondroitin generally does not cause much in the way of side effects, besides occasional mild digestive distress.

However, there is one case report of an exacerbation of asthma caused by use of a glucosamine-chondroitin product.²¹⁰

In addition, there are theoretical concerns that chondroitin might have a mild blood-thinning effect, based on its chemical similarity to the anticoagulant drug heparin. Reassuringly, there are no case reports of any problems relating to this, and studies suggest that chondroitin has at most a mild anticoagulant effect.³⁶ Nonetheless, prudence suggests that, based on these findings, chondroitin should not be combined with blood-thinning drugs, such as warfarin (Coumadin), heparin, and aspirin, except under physician supervision. In addition, individuals with bleeding problems, such as hemophilia, or who are temporarily at risk for bleeding (for example, undergoing surgery or labor and delivery) should avoid chondroitin.

Interactions You Should Know About

If you are using drugs that impair blood coagulation, such as warfarin (Coumadin), heparin, aspirin, clopidogrel (Plavix), ticlopidine (Ticlid), or pentoxifylline (Trental), do not use chondroitin except under physician supervision.