Migraine polypharmacy and the tolerability of sumatriptan: a large-scale, prospective study.Cephalalgia 1999; 19(7):668-75C
Polypharmacy (the prescription of more than one therapy for a single patient) and subcutaneous (s.c.) sumatriptan tolerability were prospectively studied in 12,339 migraineurs, each followed for up to 1 year. Inclusion/exclusion criteria were minimal and mirrored United States Imitrex labeling. Drug usage and compliance monitoring were automatically interfaced with prescription refill. Concomitant drugs were used by 79% of patients, with analgesics, antidepressants, and sedatives used most commonly. No adverse interactions between sumatriptan and neurological drugs were found, possibly reflecting relative inability of the former to cross the blood-brain barrier. No difference in cardiovascular adverse events was associated with oral contraceptive use, which was more common than expected. No other drug class influenced adverse event probability, although sample sizes for these comparisons was sometimes <400 patients. This study confirms the prevalence of polypharmacy in migraine, identifies the drugs used, and concludes that, on a population basis, the tolerability of s.c. sumatriptan, when used according to labeled instructions, is unaffected by these concomitant drugs.