Many clinical studies have been made to test the efficacy of Imitrex Sumatriptan to treat of migraine headaches. The effectiveness has bee proved in 3, randomized, double-blind, placebo-controlled studies. In these studies 87% were female patients and 97% were Caucasian, with a mean age of 40 years (range, 18 to 65 years). The study showed a remarkable decrease in headache when assessed 4 hours after dosing. It caused symptoms such as nausea, photophobia, and phonophobia. Then patients were administered a second dose of IMITREX Tablets or other medication 4 to 24 hours after the initial treatment for repeated headache. Patients were given acetaminophen in Studies 2 and 3 beginning at 2 hours after initial treatment if the migraine pain had not improved. In all 3 studies patients were administered extra medications 4 to 24 hours after the initial treatment for repeated headache or as rescue. The frequency and time to use of these additional treatments were also measured. In all studies, comparing was made among the doses of 25, 50, and 100 mg of Sumatriptan to placebo for effectualness in the treatment of migraine attacks. In 1 study, comparison was made between doses of 25, 50, and 100 mg for effectiveness test.

It was proved in all 3 trials that patients receiving IMITREX Tablets showed better results at all doses than placebo. In 1 of the 3 studies, large no of patients showed headache response at 2 and 4 hours at the 50- or 100-mg dose group than the 25-mg dose groups. The 50- and 100-mg dose groups showed similar response in the study.

In the study 1, patients showed lower occurrence of nausea, photophobia, and/or phonophobia at baseline, at 2 hours (Study 1) and at 4 hours (Studies 1, 2, and 3) using of IMITREX Tablets compared to placebo.

About 2 hours in advance in Studies 2 and 3 or 4 hours in Study 1, through 24 hours following the opening dose of study treatment, patients were given a second dose of study treatment or other medication for further treatment for pain relief.

It has not been proved if doses above 50 mg do not provide a greater effect than 50 mg. it also has not been confirmed if treatment with Sumatriptan can lead to an increase in the severity of recurrent headaches. The efficacy of IMITREX Tablets did not show difference along with aura; gender, age, or weight of the patient; relationship to menses; duration of headache prior to treatment. The concomitant use of common migraine prophylactic drugs such as tricyclic antidepressants, beta-blockers, calcium channel blockers also showed no difference in the effectiveness of this drug. No satisfactory data are available to assess the impact of race on effectiveness.

The findings of these trials can not be supported because studies showed different results when made at different times with different patients. These studies were made by different researchers, using different criteria and/or different interpretations of the same criteria, under different conditions (dose, dosing regimen, etc.).