Preclinical studies have shown that zolmitriptan is a selective serotonin 
5-HT(1B/1D) receptor agonist (triptan). Randomised, placebo-controlled, 
double-blind trials in patients with migraine have shown that zolmitriptan has 
good efficacy measured using 2 h response and pain-free rates. 
Migraine-associated symptoms, including nausea, photophobia and phonophobia, are 
also improved with zolmitriptan. Oral zolmitriptan (2.5 and 5 mg) has an onset 
of action within 45 min and efficacy is sustained in most patients who respond 
at 2 h. The orally-disintegrating zolmitriptan tablet has the advantage that it 
may be taken immediately, without the need for additional fluids, any time a 
migraine headache occurs. Patients may benefit in terms of improved efficacy 
from the convenience of the disintegrating tablet, since there is evidence that 
taking triptan therapy as early as possible in an attack is advantageous. For 
similar reasons, as well as improved efficacy, a nasal spray formulation is in 
development. Zolmitriptan is effective in the treatment of migraine associated 
with menses and migraine with aura. There is no tachyphylaxis following repeated 
doses for multiple attacks of migraine over a prolonged period of time. Compared 
to placebo, the incidence of persistent migraine headache is reduced by 
zolmitriptan and recurrent migraine headache occurs less frequently. 
Zolmitriptan has also shown efficacy in the treatment of persistent and/or 
recurrent migraine headache. Comparative clinical studies have shown overall 
that zolmitriptan has similar or superior efficacy to sumatriptan in the 
treatment of migraine. Specifically, zolmitriptan 2.5 mg was significantly more 
effective than sumatriptan 25 or 50 mg according to a number of end points, 
including headache response at 2 h. Oral zolmitriptan is also effective in the 
acute treatment of cluster headache. Zolmitriptan is generally well tolerated, 
with most adverse events being mild-to-moderate, transient and resolving without 
intervention or the need for treatment withdrawal. The consistent efficacy in 
treating all types of migraine and the choice of available formulations make 
zolmitriptan acceptable to patients and a suitable first-line therapy for the 
treatment of migraine.