Topiramate in migraine prevention: evidence-based medicine from clinical trials.

The importance of evidence-based medicine is often underestimated when migraine preventive treatments are chosen. Evidence from large, well-conducted, placebo-controlled trials of sufficient duration should be given particular consideration when evaluating the efficacy, tolerability and safety of a medication for a broad range of patients. Pizotifen, propranolol, flunarizine, amitriptyline, divalproex sodium and topiramate have all been evaluated for efficacy in migraine prevention in double-blind, placebo-controlled trials. The largest clinical programme in migraine prevention, studying these or any other agents, was comprised of 2 pivotal trials, as well as other studies, evaluating topiramate for preventive therapy in migraine. Results from these trials indicated that topiramate (100 mg/day) has proven safety and efficacy in migraine prevention. Response rates were high, and onset of action usually occurred within the first month of treatment. Therefore, topiramate has demonstrated safety and represents an effective option in the prevention of migraine, as supported by extensive clinical research.