Stimulant in Sports Supplement Linked to Exercise-Induced Stroke

Megan Brooks

May 14, 2015

β-Methylphenylethylamine (BMPEA) found in a sports supplement is likely to blame for hemorrhagic stroke in an otherwise healthy women who took the supplement before exercising, investigators say.

The case report, published online May 12 in Annals of Internal Medicine, is the first to suggest a connection between BMPEA, a chemical relative of amphetamine, and exercise-induced stroke, note Pieter Cohen, MD, from Harvard Medical School, Boston, Massachusetts, and colleagues.

The 53-year-old woman, who was previously healthy and in good physical condition, experienced sudden onset of numbness and clumsiness in her left hand about 45 minutes after starting a vigorous workout — the same workout she had repeated several times a week for a few years.

Thirty minutes before she started her regular workout, the woman reported consuming the recommended dose (13 g) of the sports supplement Jacked Power (MM Sports). It was the first time she had consumed this or any similar sports supplement.

Computed tomography of the head showed a 2-cm hemorrhage in the right parietal lobe. MRI of the brain revealed the hemorrhage, with no underlying abnormalities. Cerebral angiography showed no evidence of vasculitis, aneurysm, or other vascular malformation. Blood pressure normalized after the woman was admitted to the hospital, and it remained normal. She was discharged after 5 days with minor residual sensory symptoms.

BMPEA Likely Culprit?

The case was first reported in September 2014 in the Swedish medical journal Läkartidningen (2014;111:1782-1784).

After this initial report, the Jacked Power supplement the woman consumed was analyzed and found to contain 290 mg of BMPEA per dose.

"Exercise combined with BMPEA probably caused this patient's stroke," Dr Cohen and colleagues conclude.

BMPEA was the only unlabeled pharmaceutical or drug found. Neither BMPEA nor the botanical Acacia rigidula was listed on the supplement label. Research conducted by the US Food and Drug Administration (FDA) in 2013 established that BMPEA is not a constituent or extract of A rigidula.

Dr Cohen and colleagues note in their article that BMPEA is a synthetic compound with unknown health effects in humans. It raises blood pressure and heart rate in dogs and cats. BMPEA has been found in more than a dozen brands of supplements marketed to promote weight loss and improve athletic performance.

Last month, the FDA warned several companies to stop selling dietary supplements containing BMPEA and another stimulant, 1,3-dimethylbutylamine (DMBA). BMPEA and DMBA are similar to 1,3-dimethylamylamine (DMAA), which has already been banned by the FDA.

"Dietary supplements can legally be sold to improve workouts even when there is zero evidence that they actually work in humans," Dr Cohen said in a statement. "This creates a perverse incentive for manufacturers to introduce untested drugs into sports supplements to achieve the advertised effect. Tragically, untested stimulants can pose serious health risks to unsuspecting consumers."

The researchers encourage physicians in the United States to report all suspected serious adverse events from dietary supplements to the FDA at In Europe, physicians should report these events to the appropriate national authority, they advise.

Asked to respond to these findings, Andreas Karlsson from MM Sports told Medscape Medical News, "It's pretty hard for us to comment on the findings of the medical report as it wasn't conclusive that it was Jacked Power that caused this — it only suggested that it may be a connection between the unfortunate incident and intake of the product. And as we never have been contacted by the person or her doctor, we can’t really comment anything about that either."

Karlsson added, "We removed the product from sales over 9 months before we ever heard about the report or anything thereof — and the product hasn't been out for sale for nearly a year and a half. The removal of the product was voluntary due to marketing reasons and not because of any safety regards.

"Phenethylamines (PEAs) have been around for over 10 years in the EU [European Union] and US markets, without any negative reports to our knowledge," Karlsson noted.  

The authors have disclosed no relevant financial relationships.

Ann Intern Med. Published online May 6, 2015. Abstract


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