The efficacy of subcutaneous injection of sumatriptan in the acute treatment of migraine was assessed in a double-blind, randomized, placebo-controlled cross-over study of 27 migraine patients. In addition, the patients were asked to give information about their well-being and subjective symptoms by means of a self-administered standardized questionnaire. A total of 22 migraine sufferers received a subcutaneous (sc) injection of 8 mg of sumatriptan and 24 received placebo. Of these patients, 19 received both treatments and thus completed the study. The primary efficacy end-point was a reduction in headache severity from severe or moderate to mild or no headache at 30, 60, 90 and 120 min. An effective response to treatment was achieved within 30 min in 63% and within 60 min in 84% of patients when treated with 8 mg sumatriptan sc, compared with 11% for placebo (p less than 0.001). Sumatriptan also provided significant relief from nausea and photophobia as compared with placebo. The proportion of patients that needed rescue medication after 120 min was significantly lower (p less than 0.001) with active treatment when compared with placebo. Sumatriptan was well tolerated and the majority of adverse events were mild and transient. The most frequent symptoms were those of malaise/fatigue or numbness. No changes in blood pressure or ECG readings were observed during the treatment. Compared with placebo, subcutaneous 8 mg sumatriptan also caused a substantial improvement in general well-being as revealed by the Minor Symptoms Evaluation Profile-acute (MSEP-acute) questionnaire.(ABSTRACT TRUNCATED AT 250 WORDS)