How does glucosamine interact with other medications or foods?

Glucosamine may interact with a number of medications. Glucosamine (particularly glucosamine sulfate) may decrease the ability of acetaminophen (used to treat fever and pain) to alleviate pain. It may also cause cancer cells to become resistant to certain chemotherapy medications, such as etoposide, teniposide and doxorubicin. It may likewise interfere with the ability of diabetes medications to control blood sugar. In addition, glucosamine may exacerbate the bleeding risk in people who take medications to prevent blood clots, such as aspirin, heparin, warfarin or clopidogrel. Finally, combining glucosamine with diuretics ("water pills" such as furosemide) may exacerbate the side effects associated with glucosamine. Herbs and nutritional supplements that affect blood sugar or blood clotting mechanisms can increase the side effects of glucosamine. These include: eleuthero, fenugreek, ginger, kudzu, panax ginseng, danshen, devil's claw, garlic, gingko, horse chestnut, papain, red clover and saw palmetto. Chitosan (a nutritional supplement used for weight loss) may decrease the effectiveness of glucosamine. There are no known restrictions on food or beverage consumption while using glucosamine.