Oral sumatriptan for acute migraine.
BACKGROUND: Migraine is a common neurovascular disorder characterized by recurrent episodes of disabling headache, autonomic nervous system dysfunction, and, in some patients, neurological aura symptoms. Sumatriptan is one of a class of selective serotonin 5-hydroxytryptamine (5-HT1B/1D) agonists (triptans) thought to relieve migraine attacks by several mechanisms, including cranial vasoconstriction and peripheral and central neural inhibition. OBJECTIVES: To describe and assess the evidence from randomized controlled trials (RCTs) concerning the efficacy and tolerability of oral sumatriptan for the treatment of a single acute attack of migraine in adults. SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials (Cochrane Library, Issue 4, 2001), MEDLINE (1966 through November 2001), and reference lists of articles and books. SELECTION CRITERIA: We included double-blind RCTs comparing oral sumatriptan (100 mg, 50 mg, 25 mg) with placebo, no intervention, other drug treatments, behavioral therapy, or physical therapy for the treatment of an acute attack of migraine in adults. Trials comparing different doses of sumatriptan or dosing regimens were also included. Outcomes considered were: 2-hour pain-free response, headache relief/headache intensity, and functional disability; headache recurrence; and adverse events. DATA COLLECTION AND ANALYSIS: Data were abstracted by one reviewer and over-read by the other. The two reviewers independently assessed trial quality. Information on adverse events was collected from trial reports. MAIN RESULTS: Twenty-five trials involving 16,200 participants were included. Methodological quality was generally good. Sixteen trials were placebo comparisons and showed that sumatriptan in doses of 100 mg (14 trials), 50 mg (five trials), and 25 mg (three trials) provided significantly better pain-free response (100 mg and 25 mg only), headache relief, and relief of disability at 2 hours. Numbers-needed-to-treat (NNTs) for pain-free response at 2 hours were 5.1 (3.9 to 7.1) for the 100-mg dose (n = 2221) and 7.5 (2.7 to 142) for the 25-mg dose (n = 131); there was no significant difference between the 50-mg dose and placebo for this outcome (n = 127). For headache relief at 2 hours, NNTs were 3.4 (3.0 to 4.0), 3.2 (2.4 to 5.1), and 3.4 (2.3 to 6.6) for sumatriptan 100 mg (n = 2940), 50 mg (n = 420), and 25 mg (n = 226), respectively. Precise estimates of the efficacy of the 50- and 25-mg doses relative to the 100-mg dose could not be obtained. Adverse events were more common with sumatriptan 100 mg than with placebo (risk difference [RD] = 0.14 [0.09 to 0.20]; number-needed-to-harm [NNH] = 7.1 [5.0 to 11.1]; n = 3172). RDs for the 50- and 25-mg vs. placebo comparisons were not statistically significant. REVIEWER'S CONCLUSIONS: Oral sumatriptan has been shown to be an effective drug for the treatment of a single acute attack of migraine. It is well tolerated, though minor adverse events were not uncommon in the included trials. Other triptans were generally similar in efficacy and adverse events. Among non-triptan drugs, ergotamine + caffeine was significantly less effective than sumatriptan, and other drugs have been insufficiently studied to draw firm conclusions.