Lamotrigine versus Placebo in the Prophylaxis of Migraine with and without Aura

Lamotrigine blocks voltage-sensitive sodium channels, leading to inhibition of neuronal release of glutamate. Release of glutamate may be essential in the propagation of spreading cortical depression, which some believe is central to the genesis of migraine attacks. This study compared safety and efficacy of lamotrigine and placebo in migraine prophylaxis in a double-blind randomized parallel-groups trial. A total of 110 patients entered; after a 1-month placebo run-in period, placebo-responders and non-compliers were excluded, leaving 77 to be treated with lamotrigine (n=37) or placebo (n=40) for up to 3 months. Initially lamotrigine therapy was commenced at the full dose of 200 mg/day, but, following a high incidence of skin rashes, a slow dose-escalation was introduced: 25 mg/day for 2 weeks, 50 mg/day for 2 weeks, then 200 mg/day. Attack rates were reduced from baseline means of 3.6 per month on lamotrigine and 4.4 on placebo to 3.2 and 3.0 respectively during the last month of treatment. Improvements...