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A stimulant that athletes are barred from taking in international competition has been detected in 14 easy-to-buy supplements, according to a new study.

“The supplement label will often list a plant that it claims the drug is from,” said Dr. Pieter Cohen, an assistant professor at Harvard Medical School, who led the study. “But these are synthetic drugs.”

The substance, first developed in Europe, is known by several names: methylsynephrine, oxilofrine, and p-hydroxyephedrine, among others. It mimics the effect of amphetamines on the heart, and is not approved in the United States as either a drug or a dietary supplement. Nevertheless, it has become popular for weight loss and to enhance athletic performance.


The World Anti-Doping Agency, the Montreal-based group that works to reduce the use of drugs in sports, has banned oxilofrine from use in competitive games. Michael Kopech, a Red Sox pitching prospect, was suspended for 50 games last year after testing positive for the stimulant, although he asserts he did not intentionally take it.

Last week, the Food and Drug Administration announced it had warned seven companies that sell products containing methylsynephrine to cease selling it. The agency stopped short of calling it a drug.  


An FDA spokeswoman said staffers knew of 47 adverse reactions associated with the substance, but declined to give details. Cohen said his team, studying adverse events in the Netherlands, found links between methylsynephrine and nausea, vomiting, agitation, tachycardia, chest pain, and cardiac arrest.

Cohen’s study, published last week in the journal Drug Testing and Analysis, analyzed 27 brands of supplements labeled as containing the substance. Researchers found it in 14 different brands; dosages ranged from 0.0003 to 75 milligrams per serving. Of the brands that contained methylsynephrine, 43 percent contained what Cohen wrote was “pharmaceutical or greater dosages.”

Among the products containing the stimulant: Fastin, from Hi-Tech Pharmaceuticals; Lean Pills, from Line One Nutrition; Tummy Tuck, from TBN Total Body Nutrition; and Methyl Drive 2.0, by ANS Advanced Nutrition Systems.

Cohen said he was surprised that some manufacturers made no effort to hide their use of the stimulant and included it on their labels.

“This could very clearly have strong effects on people’s health,” he said. “There’s no law saying that the amount of each ingredient needs to be on the supplement label, so it’s very possible that the supplements contain unpredictable and unknown doses of this foreign drug.”

But Cohen views the FDA’s action as too little too late. He was intrigued by the agency’s effort to get its warning letters out ahead of his study — which he had discussed with the agency in recent months.

“It’s mind-boggling how this came about in the first place,” said Cohen. “How the companies were willing to produce it and the FDA has done nothing about it, despite the knowledge that it is in the supply chain. There have been prominent cases of athletes, even Olympic athletes, who have tested positive for it in their urine. Why did it take until 2016 for the FDA to identify something that has been openly sold in supplements for years?” Cohen said.

That’s a sore point for FDA officials, who note that their office is understaffed for their mission. “It’s a little bit of a resource challenge,” said Steven Tave, acting director of the FDA’s Office of Dietary Supplement Programs. The FDA’s supplements office has a staff of fewer than two dozen and an annual budget of less than $5 million, a spokeswoman said, to police an industry worth $30 to $40 billion.

Steve Mister, president and chief executive officer for the Council for Responsible Nutrition, the leading trade group for the dietary supplement industry, said he was troubled by the study. His group issued a bulletin April 7 warning consumers about the findings and suggesting they beware of oxilofrine.

“To see an ingredient sold in the marketplace that is patently illegal is very concerning to us,” Mister said. “The one thing we can do is putting some pressure on FDA to be more aggressive in the enforcement here. The FDA needs to enforce the law. … Just because it’s not easy or convenient to prosecute doesn’t mean they shouldn’t be out there protecting public health.”

“I work out a lot and take protein powders,” he said. “People hear about a study like this and it scares them away from the legitimate industry.”

Democratic Senator Claire McCaskill of Missouri, who has long pushed for stronger regulations and enforcement of the industry, issued a statement saying she was concerned about the study. Asking the FDA to explain why the agency had not pursued all the companies noted in the journal, McCaskill said, “We’ll keep seeing dangerous substances turn up in supplements until we get serious about oversight.”

“For years, these dietary supplements have contained an ingredient that puts the public at risk of ill health effects and puts athletes in danger of being banned from competition,” she said. “I am concerned that, once again, the FDA may have failed to act until they were faced with outside pressure. This team of researchers is doing tremendous work, but we should not be in a position of relying on them to ensure that this industry is acting responsibly.”

An earlier version of this story incorrectly stated the estimated value of the supplements industry.