Evaluation of the effectiveness of transcranial direct current stimulation for profilaxy in migrene patients with allodinia

Introduction: Allodynia is related to central sensitization that affects even simple daily living activities and increases the tendency for migraine to be more resistant to treatment and chronicity. Migraine causes loss of work force, affects social life, causes disability. The aims of prophylactic treatment of migraine are to restore the impaired normal functions, to decrease the migraine attack frequency and severity and to hinder related disability, but with various side effects. Transcranial direct current stimulation (TDCS) is a potential alternative treatment for migraine prophylaxis. Objective: to evaluate the potential efficacy of TDCS on migraine attacks in migraine patients with allodynia by a placebo-controlled randomized clinical trial, to compare it to migraine patients without allodynia. Method: Migraine patients diagnosed according to 2018 criteria of the International Headache Society were included in the study. Patients with allodynia were identified using the Allodynia Symptom Checklist. Patients with and without allodynia randomly received active or sham TDAS stimulation. For active stimulation, patients underwent three consecutive days of anodal left primary motor cortex (M1) stimulation for 2 mA, 20 minutes with cathodal electrode on the right supraorbital area. The patients were followed up for a month. Results: Among 77 migraine patients, allodynia was detected in 48 patients. After active TDCS stimulation, attack frequency, number of headache days symptomatic drug use and attack duration were all decreased. Response to TDCS treatment of patients without allodynia was significantly higher in the active group. Furthermore, allodynia score decreased significantly, and MIDAS scores improved in the treatment arm. Side effects were rare and similar to the sham group. Conclusion: It was concluded that TDCS is an effective and reliable method for migraine prophylaxis. However, administration of TDCS before allodynia occurs, which means before the development of central sensitization, will provide more effective treatment responsiveness.