Doctors caution use of weight-loss drugs

CHICAGO, Illinois (CNN) -- As part of a new study, doctors are urging people who use over-the-counter weight-loss drugs and supplements not to assume that such products are completely safe.

In a study in this week's Journal of the American Medical Association, doctors noted that these products can interact with other medications. They emphasized the need for patients to talk to their doctor about any product they are using for weight loss.

The researchers found that seven percent of all subjects surveyed used at least one non-prescription weight-loss product. The study showed 18 percent of women and eight percent of men who were trying to lose weight reported using these products.

As a further breakdown, the survey showed that of the women who were trying to lose weight, 28 percent of young obese women and eight percent of normal-weight women had taken or were taking the products.

The researchers found that one percent of respondents had used dietary supplements containing ephedra, also known as ma-huang, or herbal fen-phen. Two percent said they had used products with phenylpropanolamine (PPA), which included brand names such as Dexatrim and Acutrim.

Both have come under recent scrutiny from the Food and Drug Administration.

The FDA has requested that all drug companies discontinue marketing products containing PPA, which increases the risk of hemorrhagic stroke (bleeding into the brain or into tissue surrounding the brain).

The fen-phen diet pill combination was recalled in 1997 after being linked to heart valve damage and other medical problems. Ephedra has been linked to high blood pressure and heart problems.