Clonidine in prophylaxis of migraine.

Various drugs have been used in migraine to bring down the frequency of attacks. Recently clonidine hydrochloride, an antihypertensive agent, has been reported to be effective. The mechanism of action of this drug is not clear, but it is thought to act through its effect on tyramine metabolism. A double-blind cross-over trial using clonidine and identical-looking placebo tablets was carried out in 20 patients of migraine. There was no statistically significant difference between clonidine and the placebo in reducing the frequency of attacks, as evaluated by the non-parameteric test of Wilcoxon. No side effects of clonidine were observed.