Transcranial direct current stimulation (tDCS) was suggested to provide beneficial effects in chronic migraine (CM), a condition often associated with medication overuse (MO) for which no long-term therapy is available.

We conducted a randomized controlled trial to assess long-term efficacy of tDCS. Adults diagnosed with CM and MO were assigned to receive in a 1:1:1 ratio anodal, cathodal, or sham tDCS daily for five consecutive days, along with standardized drug withdrawal protocol with intravenous administration of dexamethasone 4 mg and ademetionine 200 mg in saline solution, and oral bromazepam 1.5 mg three times daily.

Primary outcome was 50% reduction of days of headache per month at 12 months. Co-secondary outcomes were 50% reduction of days of headache per month at 6 months, reduction of analgesic intake per month, and change in disability and quality of life, catastrophizing, depression, state and trait anxiety, dependence attitude and allodynia intensity. Patients were not allowed to take any migraine prophylaxis drug for the entire study period.

Inclusion Criteria:

• chronic migraine with medication overuse according to the International Headache Society criteria. Diagnosis was confirmed on the basis of a daily headache diary that all eligible patients filled out in the last month prior to the enrollment. Patients should have failed at least two prophylaxis therapies. Written informed consent.

Exclusion Criteria:

• known diagnosis of major depression or other major psychiatric disorders identified after psychiatric consultation, cardiac pace maker, clips for previous head surgery, cochlear implant, history of epilepsy, known idiopathic intracranial hypertension, harmful alcohol consumption, pregnancy.

sham