Vinpocetine is a synthetic derivative of the vinca alkaloid vincamine. Vinpocetine was first isolated from the plant in 1975 by the Hungarian chemist Csaba Szántay. The mass production of the synthetic compound was started in 1978 by the Hungarian pharmaceutical company Richter Gedeon. Vinpocetine has been reported to have cerebral blood-flow enhancing and neuroprotective effects, and has been used as a drug in Eastern Europe for the treatment of cerebrovascular disorders and age-related memory impairment. Vinpocetine acts as a phosphodiesterase (PDE) type-1 inhibitor in isolated rabbit aorta, Independent of vinpocetine's action on PDE, vinpocetine inhibits IKK preventing IκB degradation and the following translocation of NF-κB to the cell nucleus. Increases in neuronal levels of DOPAC, a metabolic breakdown product of dopamine, have been shown to occur in striatal isolated nerve endings as a result of exposure to vinpocetine. Such an effect is consistent with the biogenic pharmacology of reserpine, a structural relative of vinpocetine. However, this effect tends to be reversible upon cessation of vinpocetine administration, with full remission typically occurring within 3–4 weeks. Vinpocetine is generally well-tolerated in humans. No serious side effects have thus far been noted in clinical trials although none of these trials were long-term. Some users have reported headaches, especially at doses above 15 milligrams per day, as well as occasional upset stomach. The safety of vinpocetine in pregnant women has not been evaluated. Vinpocetine is not FDA approved in the United States for therapeutic use. The U.S. Food & Drug Administration (FDA) has ruled that vinpocetine, due to its synthetic nature and proposed therapeutic uses, was ineligible to be marketed as dietary supplement under the Federal Food, Drug, and Cosmetic Act (FDCA).