Lack of Interaction Between Oral Dihydroergotamine and the Novel Antimigraine Compound Zolmitriptan in Healthy Volunteers

Twelve healthy volunteers participated in a double-blind, randomised, balanced, two-period, crossover study in which they received 5mg oral dihydroergotamine or placebo twice a day for 10 days, with a washout of at least a week between periods. On the morning of the last day of each period they also received a 10mg dose of zolmitriptan (formerly known as 311C90). There were no significant differences in baseline (pre-zolmitriptan) or post-zolmitriptan blood pressures between the two occasions and dihydroergotamine had no significant effect on any pharmacokinetic parameters of zolmitriptan or its metabolites. There were no clinically significant changes in ECGs and adverse experiences were typical of 5HT1b/1d agonists. These data suggest that zolmitriptan can be used in conjunction with oral dihydroergotamine without special precautions.