The US Department of Health and Human Services announced that it is taking immediate steps to push for a warning label to be put on all ephedra-containing products.

"We want to caution all Americans, particularly athletes and those who engage in strenuous activities about using dietary supplements that contain ephedra. I would not take this or give it to my family. I don't know why anyone would take the risk," said HHS Secretary Tommy Thompson.

The announcement followed recent headlines linking the dietary supplement to the February 17th death of Baltimore Orioles pitching prospect Steve Bechler. Bechler collapsed during spring training and had been taking an ephedra-containing supplement, three times daily.

Ephedra, also known as ma huang, is contained in some supplements touted for weight loss. The herb affects the cardiovascular and central nervous systems, and has already been linked to the risk of seizure, heart attack and sudden death, even in healthy people.

The HHS action was based on the results of a RAND Corporation study released here.

According to US Food and Drug Commissioner, Dr. Mark McClellan, the HHS-commissioned report found limited benefit from the use of ephedra and also found that the stimulant could have a potentially dangerous effect on the nervous systems and heart.

The news of Bechler's death spurred members of Congress to ask the US Food and Drug Administration (FDA) for immediate action.

"Because existing evidence suggests that the use or misuse of botanical ephedrine alkaloids may cause serious, life-threatening conditions, we would urge you to immediately consider requiring all such products to bear a warning label," members of the House Committee on Energy and Commerce urged McClellan in a letter dated February 28.

The committee members said they would also open their own investigation, while noting that the government's investigative arm reported in July 1999 that there was evidence that ephedra could boost blood pressure, cause a rapid heart rate and cause death of heart cells, in addition to other problems.

Just this month a group of researchers reported that ephedra is linked to more than 100 times as many reports to US poison control centers as other herbs.

Based on an analysis of reports to the American Association of Poison Control Centers, researchers found that ephedra-containing products made up 64 per cent of the reactions to herbal products reported in the US in 2001, even though less than 1 per cent of herbal products sold that year contained ephedra.

But industry representatives insist that the use of the herb is safe if used according to the label.

"Our position has always been that ephedra is safe if used as directed and can offer significant benefits," a spokesman for the Ephedra Education Council, a group formed by members of the American Herbal Products Association, said.