We performed this systematic review and meta-analysis to evaluate the tolerability and efficacy of intranasal sumatriptan, a selective serotonin agonist, compared to placebo or other migraine therapeutics for the treatment of acute migraine attacks. We searched PubMed, SCOPUS, Embase, and Cochrane CENTRAL for relevant randomized controlled trials (RCTs). Data were extracted from eligible studies and pooled as risk ratios (RR), using RevMan software. We performed subgroup and meta-regression analyses for different doses and treatment endpoints. Sixteen RCTs (n = 5925 patients) matched our inclusion criteria. The overall effect-estimate showed that intranasal sumatriptan was superior to placebo in terms of pain relief (RR = 1.70, 95% CI [1.31, 2.21], p < 0.0001) and headache relief (RR = 1.58, 95% CI [1.35, 1.84], p < 0.00001) at 2 h. Although sumatriptan was superior to placebo in terms of headache relief at 30 min (RR = 1.31, 95% CI [1.08, 1.59], p = 0.005), no significant difference was found between both groups in terms of the frequency of pain-free participants at 30 min (RR = 1.18, 95% CI [0.49, 2.88], p = 0.71). Subgroup analysis and meta-regression models showed that increasing the dose of sumatriptan reduced the time needed for headache relief; however, this clinical improvement with higher doses was associated with more frequent adverse events in comparison to smaller doses. In conclusion, intranasal sumatriptan is effective for the treatment of acute migraine attacks. However, it was associated with a six-fold increase in the risk of taste disturbance, compared to the placebo. Future RCTs are recommended to provide head-to-head comparison of different administration routes and drug formulations of sumatriptan.
Keywords: Headache; Intranasal; Meta-analysis; Migraine; Sumatriptan.