According to the International Classification of Headache Disorders (1, 2), the criteria for the diagnosis of medication overuse headache include Headache that occurs ≥ 15 days a month in a patient with a preexisting headache disorder Regular overuse of one or more medications taken for acute treatment of headache for > 3 months (medications include ergotamine, triptans, opioids, or mixed analgesics taken ≥ 10 days a month or a single nonopioid analgesic such as acetaminophen, aspirin, or another NSAID taken ≥ 15 days / month) No other headache type that better accounts for the clinical presentation Medication overuse headache must be differentiated from the primary headache disorder, which typically causes concurrent symptoms.