A 13-year tally of deaths and poisonings from ephedra show a spectacular decline after the U.S. Food and Drug Administration banned the sale of weight loss products containing the herb in 2004. 

"The number of poisonings resulting in major effects or deaths has decreased by more than 98% since 2002. The 2004 FDA ban has proved to be a very effective means of limiting the availability of ephedra and therefore its potential toxicity in the United States," Illinois researchers report in the May 28 New England Journal of Medicine.

It was the first dietary supplement to be banned.

"I used to see patients with a lot of ephedra problems in the late 1990s and early 2000s. I haven't seen one literally in 10 years," coauthor Dr. Jerrold Leikin, director of toxicology at NorthShore University HealthSystem in Evanston told Reuters Health in a telephone interview.

"It's the eradication -- you can almost use that word -- of this substance within a relative short period of time -- a few years," he said. "It was expected, but the extent is quite surprising. And remember, this was not a drug. This was an over-the-counter dietary supplement. There's been very few studies looking at the effect of an FDA ban on dietary supplements."

Ephedra, also known as ma huang, was the chief ingredient in many weight-loss and energy-enhancement products in the U.S. The herb was known to produce modest short-term weight loss but it was killing people.

It has been linked to heart attack, stroke, seizure, high blood pressure, and heart rhythm problems. It was held responsible for the death of Baltimore Orioles pitching prospect Steve Bechler in 2003. It was especially dangerous when used in conjunction with caffeine.

The ban was implemented in April 2004, overturned by the industry in 2005 but ultimately upheld by the U.S. Court of Appeals in 2006. Prior to the ban, industry groups were saying the substance had been used by 12 million people.

Using data from the National Poison Data System, the researchers found that ephedra poisonings peaked at 10,326 in 2002 and then began a significant decline to 180 by 2013.

Major effects, defined as hospitalization usually requiring critical care, peaked the same year, at 108, one year after the system began collecting ephedra data. By 2008, such reports were down to three or fewer per year.

The number of deaths peaked later -- at seven in 2004. There had been five, three and six the previous years. After the ban, there was one death in 2005 and 2007. There were none in 2006 and in the years after 2007.

"What kind of surprised us was the near-completeness of the decrease in toxicity, how it went from 8,000 to 10,000 down to literally a few dozen calls to the poison center," Dr. Leikin said.

He speculated that the initial declines seen just before the ban went into effect could have been the result of natural fluctuations in the number of poisonings and major effects.

Dr. Stephen Barrett, a retired psychiatrist who has been following the dietary supplement industry for decades, said he was please to see evidence "that action by the FDA has reduced the harm caused by an herbal product."

Unfortunately, said Dr. Barrett, who operates the Quackwatch.org, website, the FDA's "ability to act quickly and to ban other dangerous products has been severely crimped by the 1994 Dietary Supplement Health and Education Act. This awful law classifies herbal products as dietary supplements and prevents the FDA from banning them without proof that they have caused deaths and/or serious injuries. That’s backwards."

He said "the law should require that herbal products sold for alleged health purposes be proven safe and effective BEFORE marketing."