Migraine prophylaxis by anodal transcranial direct current stimulation, a randomized, placebo-controlled trial.

Migraine is a common headache syndrome in adult populations. Prophylaxis is necessary to improve the quality of life but some patients with migraine have contraindication or suffer from side effects of medication, and therefore, establishing non-medical, neuromodulatory approaches is necessary. Past evidence had shown that consecutive motor cortex (M1) stimulation with anodal transcranial direct current stimulation (tDCS) was effective to relieve central pain.To determine whether 20 consecutive days of the left M1 can be an effective prophylactic treatment for migraine.Forty-two episodic migraine patients who had never received any prophylactic treatment, failed prophylactic treatment, or discontinued treatment due to adverse events were recruited in the present study. Patients were randomized to receive either active tDCS or sham tDCS 1mA, 20 m for 20 consecutive days and followed up for 12 weeks. Differences between and within groups were determined using repeated measures ANOVA. The level of significance was set at p < 0.05.Thirty-seven patients participated in the final analyses (active: n = 20, sham: n = 17). Between-groups comparison of attack frequency, pain intensity, and abortive medications used were performed at 4, 8, and 12 weeks after treatment. The results showed statistically significant reduction in attack frequency and abortive medications at week 4 and 8 after treatment. The pain intensity was statistically significant reduced at week 4, 8, and 12. All patients tolerated the tDCS well without any serious adverse events.The present study suggests that anodal M1 tDCS may be a safe and useful clinical tool in migraine prophylaxis. The mechanism of action of anodal tDCS on neuromodulation in migraine patients needs further investigation.