A Food and Drug Administration ban on herbal Fen Phen and other ephedra products will officially go into effect today. The FDA announced the ban on December 30, 2003, citing a risk of serious and potentially deadly side effects for consumers taking the herbal supplements.

Ephedra, also known as ma huang, is a dietary supplement containing the active ingredient ephedrine. Supplements containing ephedra have been sold to consumers as an over-the-counter weight loss product.

After the diet drug combination Fen Phen was recalled in September 1997, many consumers switched to over-the-counter supplements containing ephedra that were marketed as “herbal Fen Phen.”

The FDA has received over 1,000 adverse event reports linked to herbal Fen Phen and other ephedra supplements, including at least 150 deaths. Researchers say that ephedra can increase blood pressure, putting consumers at risk of a number of serious conditions, including heart attack and stroke. In addition, the FDA says that there is no clear evidence that ephedra helps with anything but modest weight loss.

Products which have been known in the past to contain ephedra include: Metabolife, Ripped Fuel, Stacker 3, Hydroxycut and Xenadrine RFA-1.