Lack of effect of flunarizine on the pharmacokinetics and pharmacodynamics of sumatriptan in healthy volunteers.

Twenty-four healthy subjects completed a double-blind, placebo controlled, parallel group study to evaluate the effect of treatment with flunarizine on the pharmacokinetics and pharmacodynamics of sumatriptan, a 5HT1-like agonist. Subjects received a single oral 200 mg dose of sumatriptan on the eighth day of a once daily treatment with either flunarizine 10 mg or matching placebo. There were no significant differences between treatments in relation to Cmax (82.3 ng ml-1 in the absence and 81.4 ng ml-1 in the presence of flunarizine), AUC (368 ng ml-1 h in the absence and 360 ng ml-1 in the presence) and elimination half-life (2.2 h in the absence and 2.4 h in the presence of flunarizine) of sumatriptan. Similarly pretreatment with flunarizine was not found to have any clinically significant effect on the pharmacodynamics of sumatriptan as measured by pulse rate, blood pressure and ECG.