Repeated, periodic attacks of one-sided throbbing headache made worse by activity and lasting 4-72 hours. The headache is accompanied by nausea, vomiting, photophobia, and/or phonophobia. There is often an early warning phase involving mood swings, food cravings, excess energy, and cognitive impairment for several hours prior to the onset of headache. Once the headache has resolved, it is typically followed by several hours of fatigue, cognitive impairment, allodynia, and/or depressed mood. Migraine is often thought of a severe headache. While this is true for many, not all migraine attacks involve severe pain. In fact, it is possible to experience ancephalgic (silent) migraine attacks in which there is no pain at all. It is the accompanying symptoms that distinguish migraine from other types of headache disorders.
Patients with a pre-existing primary headache who in association with medication overuse develop a new type of headache or a marked worsening of their pre-existing headache that, in either case, meets the criteria for 8.2 Medication-overuse headache (or one of its subtypes) should be given both this diagnosis and the diagnosis of the pre-existing headache. Patients who meet criteria for both 1.3 Chronic migraine and 8.2 Medication-overuse headache should be given both diagnoses.