Nylidrin
Nylidrin, also known as buphenine belongs to the category of drugs called vasodilators, which relax blood vessels and increase blood flow. Nylidrin is a peripheral vasodilator. Some studies show the evidence of improving cognitive impairment in selected individuals, such as geriatric patients with mild to moderate symptoms of cognitive, emotional and physical impairment.  Nylidrin is utilized to treat several disorders that may benefit from increased blood flow (for example, certain mental disorders, blood vessel disease due to diabetes, frostbite, night leg cramps, and certain types of ulcers). This medication works by dilating (widening) blood vessels to help increase blood flow (improving circulation) throughout the body, including the extremities and central nervous system. This effect may help to improve memory/judgment, improve walking ability, and support the healing of frostbite/ulcers.  FDA has considered nylidrin as "lacking substantial evidence of effectiveness" in cerebral ischemia, cerebral arteriosclerosis, and other cerebral circulatory insufficiencies. Therefore, the FDA has withdrawn nylidrin from the U.S. market.