By Lisa Rapaport

(Reuters Health) – Many supplements marketed for brain health may contain piracetam, an ingredient not proven effective for preventing or easing dementia or cognitive impairment and not approved for sale in the U.S., researchers say.

In an analysis of five products purchased online, researchers found that four contained piracetam, sometimes in dangerously high amounts. The fifth, which was labeled and sold as piracetam, contained no detectable amount of the drug.

The U.S. Food and Drug Administration (FDA) warned last February that so-called cognitive enhancement supplements may be ineffective, unsafe and could prevent patients from getting the correct diagnosis and treatment.

“Any products making unproven drug claims could mislead consumers to believe that such therapies exist and keep them from accessing therapies that are known to help support the symptoms of the disease, or worse as some fraudulent treatments can cause serious or even fatal injuries,” then-FDA Commissioner Dr. Scott Gottlieb said in a statement.

While the FDA didn’t single out piracetam, it’s one of the more common and worrisome ingredients in unapproved cognitive enhancement supplements, researchers note in JAMA Internal Medicine.

For the study, Dr. Pieter Cohen of Somerville Hospital Primary Care in Massachusetts and colleagues searched online for supplements with piracetam in the description or ingredient list, then ordered samples to test in a lab and see how much of the ingredient they contained.

They tested a total of 10 samples from four manufacturers. The amount of piracetam contained in the recommended servings ranged from 831 mg to 1,542 mg. In the four products that contained the ingredient, the amount of piracetam ranged from 85% to 188% of the amount claimed on the label.

Following the manufacturers’ recommendations, consumers could be exposed to quantities ranging from 831 mg to 11,283 mg of piracetam per day, depending on the brand consumed, the researchers note.

In Europe, where piracetam is prescribed for disorders including dementia and cognitive impairment, tablets are typically 800 mg or 1,200 mg and daily dosing tends to be 2,400 mg to 4,800 mg, the study team notes.

At doses lower than researchers found in some supplements available for purchase in the U.S., side effects of piracetam include anxiety, insomnia, agitation, depression, drowsiness and weight gain, the authors write.

Side effects may be worse at higher doses, although the precise risks are unknown, they point out.

Beyond the small number of samples tested, other limitations of the study include the possibility that amounts of piracetam in the supplements might vary over time, the study authors note.

Even so, consumers should steer clear of piracetam supplements, given the lack of evidence that it helps cognition and the potential harmful side effects, the researchers conclude.

“Clinicians should advise patients that supplements marketed as cognitive enhancers may contain prohibited drugs at supratherapeutic doses,” the study authors warn.

SOURCE: JAMA Internal Medicine, online November 25, 2019.