Flunarizine is a non-selective calcium antagonist. It distributes preferentially in the adipose tissue and passes the blood brain barrier. Numerous controlled clinical studies have established that flunarizine is efficacious in migraine prophylaxis, including double-blind studies in which the drug was compared with placebo or other antimigraine drugs. To avoid side effects a special schedule or administration is necessary. Flunarizine has no myogenic effect on smooth muscle cells of the vessles. It is said to be the only calcium antagonist able to protect brain cells against hypoxic damage. In addition, the considerable body of information which shows flunarizine capable of directly influencing the central nervous system, suggests that the drug's anti-migraine action may depend on its ability to influence central phenomena.