, according to an analysis of products sold online.
Sales of so-called ‘brain enhancement’ supplements exceeded $640 million in 2015 in the United States alone, but little is known about the risks of these dietary supplements,, of the Cambridge Health Alliance in Somerville, Mass., and his coauthors wrote in a research letter published online Nov. 25 in .
Piracetam is prescribed in many European countries for cognitive impairment and other disorders, the authors said. There is limited evidence for its efficacy, and the United States does not permit its sale as a dietary supplement.
Using the search terms “piracetam” and “dietary supplement,” researchers identified five brands of supplements sold online and analyzed 10 samples from these. Their chemical analysis revealed that eight samples from four brands contained piracetam, ranging from 831 mg to 1,452 mg per recommended serving size, and 85%-118% of the amount on the product’s label.
“Our findings demonstrate that, even after the FDA rejected an application to market piracetam as a new supplement ingredient, the drug was nevertheless introduced into the marketplace,” the authors wrote.
The authors calculated that, if consumers followed the recommended dosage on the labels of these products, they could be exposed to up to 11,283 mg of piracetam per day.
For comparison, prescription piracetam in Europe is commonly found in 800-mg and 1,200-mg tablets, and the recommended daily dose for cognitive disorders ranges from 2,400 to 4,800 mg per day, adjusted for renal function.
The authors commented that piracetam is associated with side effects at pharmaceutical dosages, including anxiety, insomnia, agitation, depression, drowsiness, and weight gain. However, the risk associated with higher doses, particularly in the elderly and those with renal insufficiency, are unknown.
“Until the law governing supplements is reformed such that products adulterated with drugs can be effectively removed from the market, clinicians should advise patients that supplements marketed as cognitive enhancers may contain prohibited drugs at supratherapeutic doses,” the authors wrote.
One author declared research support from two organizations unrelated to the study. No conflicts of interest were declared.
SOURCE: Cohen P et al. JAMA Int Med. 2019 Nov 25. .