Vinpocetine

Vinpocetine (ethyl apovincaminate) is a synthetic derivative of the vinca alkaloid vincamine. Vincamine is extracted from either the seeds of Voacanga africana or the leaves of Vinca minor (lesser periwinkle). Vinpocetine (ethyl apovincaminate) is a synthetic derivative of the vinca alkaloid vincamine. Vincamine is extracted from either the seeds of Voacanga africana or the leaves of Vinca minor (lesser periwinkle). Vinpocetine has been clinically indicated in Europe for treatment of cerebrovascular disorders such as stroke and dementia for over three decades. Use during pregnancy may harm the baby or result in miscarriage. Vinpocetine is not approved for any therapeutic use in the United States. The FDA has ruled that vinpocetine, due to its synthetic nature and proposed therapeutic uses, is ineligible to be marketed as dietary supplement under the Federal Food, Drug, and Cosmetic Act. Despite this, vinpocetine remains widely available in dietary supplements often marketed as nootropics. The sale of vinpocetine as a supplement is banned in Australia, New Zealand, and Canada due to “potential harmful nootropic characteristics”. Evidence does not fully support a benefit in either dementia or stroke. As of 2003, three controlled clinical trials had tested 'older adults with memory problems'. Adverse effects of vinpocetine include flushing, nausea, dizziness, dry mouth, transient hypo- and hyper-tension, headaches, heartburn, and decreased blood pressure. FDA issued a statement in 2019 warning that 'vinpocetine may cause a miscarriage or harm fetal development'. Vinpocetine has been implicated in one case in the induction of agranulocytosis, a serious condition in which granulocytes are markedly decreased. Some people have anecdotally noted that their continued use of vinpocetine reduces immune function. Commission E warned that vinpocetine-reduced immune function could cause apoptosis (cellular death) in the long term. Vinpocetine’s mechanism of action has been postulated to involve three potential effects: blockage of sodium channels, reduction of cellular calcium influx, and antioxidant activity. Studies have also suggested that vinpocetine can inhibit phosphodiesterase (PDE) type-1 inhibitor in isolated rabbit aorta; inhibit IKK in vitro, preventing IκB degradation and the following translocation of NF-κB to the cell nucleus; and increase DOPAC, a metabolic breakdown product of dopamine, in isolated striatal nerve endings of rats. The inclusion of vinpocetine in dietary supplements in the U.S. has come under scrutiny due to the lack of defined dosage parameters, unproven short- and long-term benefits, and risks to human health. In the U.S., vinpocetine supplements are marketed as sports supplements, brain enhancers, and weight loss supplements. A 2015 analysis of 23 brands of vinpocetine dietary supplements sold at GNC and Vitamin Shoppe retail stores reported widespread labeling errors. Only 6 of the 23 supplement labels (26%) provided consumers with accurate dosages of vinpocetine (ranging from 0.3 to 32 mg per recommended daily serving), while 6 of 23 (26%) contained no vinpocetine at all, despite their labels claiming that the ingredient was in them. In total, 9 of the 23 products tested were mislabeled and 17 of 23 (74%) did not provide any information on the quantity of vinpocetine. In response to the study, then-Senator Claire McCaskill, while at the time serving as the top Democrat on the Senate Special Committee on Aging, urged the FDA to suspend sales of vinpocetine supplements and asked 10 retailers to voluntarily stop selling vinpocetine products. McCaskill stated 'The way we regulate these supplements isn’t working—and it’s putting the lives and well-being of consumers at risk. We’ve seen products with false labels, tainted ingredients, wildly illegal claims, and, now, products containing synthesized ingredients that are classified as prescription drugs in other countries.' A 2016 analysis of eight brands of vinpocetine supplements sold in the U.S. found that the amount of vinpocetine contained was highly variable, ranging from 0.6 to 5.1 mg per serving, with most of the product labels providing no information on the amount of vinpocetine. Only one of the products tested contained the amount of vinpocetine that was specified on the label (1.070 mg per serving). The authors of the study noted that the lack of proper labeling regarding the amounts of vinpocetine in the products could pose a risk of adverse effects to consumers.