Several dietary supplements that claim to boost brainpower and protect against memory loss contain various amounts of piracetam, a drug not approved for that use in the United States, according to a study published recently in JAMA Internal Medicine.
Some of the common side effects of piracetam include diarrhea, anxiety, insomnia, agitation, drowsiness, weight gain and depression — side effects that people may not realize are being caused by the supplement. In addition, the effects of the drug on older people with kidney problems are unknown.
This study’s findings are yet another reminder of the potential dangers facing the 50 percent or so of American adults who use dietary supplements. As I’ve noted here before, dietary supplements, which include vitamins, minerals, botanicals, amino acids and enzymes, are not supposed to be used for the treatment or prevention of disease. The U.S. government classifies them as a category of food (thanks to the supplement industry’s successful lobbying of Congress). Supplements are not required, therefore, to undergo testing for effectiveness or safety before they go on the market.
So-called brain enhancement supplements — known as “nootrophics” — have become particularly popular in the United States in recent years. American consumers spent more than $640 million on such supplements in 2015 alone, note the authors of the new study. Many of those consumers are hoping to ward off dementia.
But, as the Food and Drug Administration (FDA) has warned, nootrophics “may be ineffective, unsafe, and could prevent a person from seeking an appropriate diagnosis and treatment.”
In some European countries, piracetam is prescribed for cognitive impairment and other disorders. Almost two decades ago, however, a major review of the scientific literature by Cochrane, a nonprofit global organization of independent scientific investigators, found only low-quality evidence (and not very much of it) for the drug’s effectiveness.
No good evidence in support of the drug’s “brain-boosting” abilities has emerged since then.
“The FDA has determined that piracetam is not permitted to be sold as a dietary supplement,” the authors of the current study point out, “but enforcement is limited, and piracetam supplements remain available for sale.”
Right on the labels
For the study, a team of researchers led by Dr. Pieter Cohen of Harvard Medical School, made online purchases of all products with the terms “piracetam” and “dietary supplement” listed on their labels. They found five brands of supplements that met those criteria.
The researchers tested two samples (from two separate bottles) of each brand to see how much piracetam they contained. They found that the quantity of the drug in four of the products ranged from 831 milligrams to 1,542 milligrams per tablet.
Those amounts are concerning, for they can expose people to doses that exceed the standard dose recommended by the European countries that allow the drug to be prescribed for dementia. Indeed, the dose contained in one of the supplements tested by the Harvard researchers was two to four times higher than that recommended in those countries.
Interestingly, the fifth supplement tested contained no piracetam — even though its label said each tablet contained 700 milligrams of the drug.
The study comes with several limitations. Most notably, the researchers tested only dietary supplements that openly listed piracetam on their labels. Other supplements may also contain the drug.
Furthermore, the researchers analyzed the contents of only two samples of each product. If larger quantities had been tested, the range in the amounts of piracetam in the individual brands might have been different.
Needless to say, the study’s results are deeply troubling.
“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,” Cohen and his colleagues conclude. “Despite FDA warning letters, the products remain on the market.”
“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,” they add.
FDA: You’ll find an abstract of the study on the JAMA Internal Medicine website, although the full paper is behind a paywall. UPDATE: The journal has made it possible to read the article in full at this guest link.