MS Speaks

Russian Drugs Pass as Supplements in U.S.

Two pharmaceutical-grade drugs are being marketed as brain-boosting supplements


 
by Kristina Fiore
Staff Writer, MedPage Today


Both vinpocetine and picamilon are prescribed as cerebrovascular drugs in several other countries, but are sold as nutritional supplements in the U.S. and marketed to improve focus and memory. Neither is a simple botanical extract: vinpocetine is the product of heavy refinement of the alkaloid vincamine (found in the lesser periwinkle Vinca minor), while picamilon has no known natural source and is only produced synthetically.

There's been increasing interest in nootropics -- substances that boost cognitive function -- for healthy patients to prevent disease, as well as for patients with neurological or muscle diseases, including Alzheimer's, dementia, and multiple sclerosis (MS), but in some instances these compounds may cause more harm than good.

Vinpocetine, for instance, has been observed to disrupt myelin repair, which could be especially problematic for MS patients.

In an analysis of the brands of these supplements sold at GNC and the Vitamin Shoppe, many delivered the same daily doses as when the drug is prescribed pharmacologically, Pieter Cohen, MD, of Harvard Medical School and the Cambridge Health Alliance, and colleagues reported in Drug Testing and Analysis.

"The FDA has permitted an unapproved new drug with unproven efficacy and known adverse effects to be sold directly to consumers," Cohen wrote in an wrote in an accompanying commentary in Mayo Clinic Proceedings about vinpocetine. "The FDA should not permit unapproved drugs, even semisynthetic derivatives of natural compounds, to be sold as dietary supplements."

Vinpocetine is prescribed in Russia, China, Germany, and other countries for acute stroke and cognitive impairment, but it has never been approved by the FDA as a prescription drug.

Data on its neuroprotective effects are conflicting, while its known side effects include flushing, headaches, and decreased blood pressure.

In 1997, a manufacturer submitted a new dietary ingredient notification to FDA, and since then it has been permitted as a supplement.

Cohen said the agency "may have assumed that vinpocetine was a botanical extract, but it is not." It can be synthesized from vincamine, which is found in the leaves of the lesser periwinkle, but it is the result of heavy processing and has never been identified by itself in any plant.

Nor is picamilion found in any known plant. It is fully synthetic and was first developed by Russian investigators to increase CNS levels of GABA for treating anxiety and seizures. It's currently used in Russia for various neurological conditions.

Unlike vinpocetine, it has never been submitted to the FDA, Cohen said.
For their study, Cohen and colleagues analyzed 23 brands of vinpocetine and 31 brands of picamilon supplements to determine the accuracy of their labels. They used the ultra-high performance liquid chromatography photodiode-array method to quantify these ingredients.

Only 26% of the vinpocetine brands provided consumers with accurate information about the dose of the ingredient in their product, Cohen said.
They found that 17 of the 23 vinpocetine brands contained quantities ranging from 0.3 mg to 32 mg per recommended daily serving -- with many of these falling in the pharmaceutical dose range of the drug, which is 5 mg to 40 mg. There was no vinpocetine in six samples.

They also compared two samples of Vinca minor and found the alkaloid vincamine, but there was no vinpocetine at all, they reported.
Of the 31 brands of picamilon supplements, 30 had quantities ranging from 2.7 mg to 721.5 mg per recommended daily serving. Prescription doses range from 50 mg to 200 mg.

"New drugs can bypass the rigorous drug approval process and can be sold directly to consumers without FDA approval," Cohen said.

The study was limited because the researchers only sampled one of each supplement, but Cohen said this kind of practice wouldn't be unusual in a system that doesn't require companies to report how much active ingredient is in the product or what its side effects might be.

He and his team concluded that the findings show that drugs prescribed as pharmaceuticals in other countries are being sold openly in dietary supplements in the U.S.

"It's pretty widely understood by both the FDA and industry that if you have to synthetically change a botanical compound, then it's a drug," Cohen told MedPage Today. "The Dietary Supplements Health and Education Act wasn't designed to regulate these kinds of products."
"Remarkably," he added, "the FDA has done nothing to intervene in the sale of these brain enhancing supplements containing unapproved drugs."
Cohen disclosed no financial relationships with industry.