Diet drugs off the market

FDA Consumer, Nov-Dec, 1997

Due to new evidence suggesting that Redux (dexfenfluramine) and Pondimin (fenfluramine) are the likely cause of heart valve problems, the manufacturers have withdrawn the obesity drugs from the market at FDA's request.

People should stop use of either drug and discuss their treatment with their doctors.

The evidence comes from doctors who performed echocardiography to evaluate heart valve function in patients taking the drugs, FDA announced Sept. 15. About 30 percent of the patients had abnormal readings, even without symptoms. This percent is much higher than expected.

FDA did not request withdrawal of phentermine, the third widely used obesity drug. The combination of fenfluramine and phentermine, popularly known as "fen-phen," has been used off-label for obesity. (See "Mixing Diet Drugs Calls for Caution" in the Updates section of the September-October 1997 FDA Consumer.)

For more information on this topic, go to http://www.fda.gov/cder/news/ fenphenpr81597.htm on FDA's Web site.