Nurseweek/Healthweek | Diet pills taking more hits from two med journals

Diet pills taking more hits from two medical journals

posted 9-10-97

Two recent studies showing the health threats of popular diet drugs have prompted calls for a moratorium on the use of such drugs for cosmetic purposes and for prominent warning labels on weight-loss pills.

The first study, which was published in the Aug. 27 Journal of the American Medical Association, showed that two drugs used by millions to combat obesity disrupt brain functioning in laboratory animals.

JAMA reported that animals given the drugs dexfenfluramine and fenfluramine, sold under the brand names Redux and Pondimin in the United States, exhibited a disruption in levels of serotonin, a neurotransmitter used to relay cognitive information and regulate mood and impulses.

Researchers also found the drugs could cause primary pulmonary hypertension. The study was based on a new analysis of 71 previous studies performed on animals.

Researchers cautioned they don’t know whether clinical trials on humans would show the same disruption of serotonin levels as indicated in studies on rats and primates.

On Aug. 28 the New England Journal of Medicine cited 58 new cases of heart valve damage in patients who have used fen-phen, the diet pill combination that Mayo Clinic researchers linked to heart disease in July.

Fen-phen is a physician-prescribed combination of fenfluramine and phen ter mine. Both are approved for short-term weight loss, but their combination has not been tested by the FDA.

Drug companies have raised the possibility that obesity itself, not drugs to treat the condition, may be causing heart disease.

Although researchers said findings on all the drugs are inconclusive, an editorial in the New England Journal of Medicine called for a moratorium on the use of diet drugs for cosmetic purposes.

The Federal Drug Administration said it would require drug makers to include prominent package and label warnings about the potential health risks associated with weight loss pills.

The agency may take further steps to change recommended dosages or length of time the drugs can be safely prescribed, a spokesperson said.