'Fenphen' has serious long-term effects

PROVO, Utah, Nov. 6 (UPI) -- People who stopped using the appetite suppressant fenfluramine 11 years ago had damaged heart valves up to seven years later, U.S. researchers said.

Charles Dahl of the Central Utah Clinic led a team of researchers who studied the heart condition of 5,743 former fenfluramine users.

Fenfluramine and the closely related dexfenfluramine were widely prescribed as half of a so-called "fen/phen" drug combination used to combat obesity. In 1997, the drug was banned in the United States due to fears over its links to heart conditions.

The authors found 0.44 percent of former fenfluramine users had valve surgery as a result of the use of fenfluramines. The risk was approximately seven fold compared with those who hadn't taken the drug, the study said.

"This is probably a conservative estimate, as another study has shown that there exists a 17- to 34-fold excess of clinically apparent -- presumably severe -- valvular disease in persons who had used fenfluramines for four months or longer," Dahl said.

The study is published in the journal BMC Medicine.