Calcium antagonists in migraine and vertigo. Possible mechanisms of action and review of clinical trials.
Three primary mechanisms have been suggested as an explanation of migraine; a neuronal event, a vascular event and a mechanism focussing on the trigeminal nerve and its supply to intra- and extracranial blood vessels. None of these theories has been adequately proven yet. A neuronal point of impact, rather than a vascular one, seems to be responsible for migraine prophylaxis with calcium antagonists. Primarily vasoactive substances such as nimodipine are not or only marginally effective, whereas flunarizine with a limited vascular activity is effective. Data on other calcium antagonists are insufficient to conclude on a migraine-prophylactic activity. The only calcium antagonist that has been extensively tested for vertigo is flunarizine. In placebo-controlled trials, the drug showed to be effective in labyrinthine vertigo. The mechanism behind this effect is unclear.
Olesen
J
J
Department of Neurology, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark.
D002118:Calcium / Q000502:physiology; D002121:Calcium Channel Blockers / Q000627:therapeutic use*; D005444:Flunarizine / Q000627:therapeutic use*; D006801:Humans; D008881:Migraine Disorders / Q000188:drug therapy* / Q000378:metabolism / Q000503:physiopathology; D014717:Vertigo / Q000188:drug therapy* / Q000378:metabolism / Q000503:physiopathology
D002121:Calcium Channel Blockers; D005444:Flunarizine; D002118:Calcium