Classification of Headache

Primary Headache Disorders

The International Headache Society recommends that primary headaches be divided into three main types: migraine, tension-type headache, and cluster headache, with migraine without aura requiring at least 5 attacks meeting specific criteria, including duration of 4-72 hours, unilateral location, pulsating quality, moderate or severe pain intensity, and aggravation by routine physical activity 2
The American Academy of Neurology suggests that migraine with aura requires at least 2 attacks with one or more fully reversible aura symptoms, including visual, sensory, speech/language, motor, brainstem, or retinal symptoms, with at least three of six characteristics, including gradual spread of symptoms over ≥5 minutes, succession of symptoms, and duration of 5-60 minutes 2
The International Headache Society recommends that chronic migraine be diagnosed when headache occurs on ≥15 days/month for >3 months, with at least 5 attacks fulfilling criteria for migraine without aura and/or migraine with aura, and on ≥8 days/month for >3 months, headache meets migraine criteria or is believed by the patient to be migraine at onset and relieved by a triptan or ergot derivative 2
Tension-type headache is characterized by bilateral location with pressing/tightening quality, mild to moderate intensity, and absence of nausea or vomiting, according to the American Academy of Family Physicians 5

The International Headache Society suggests that medication-overuse headache requires headache on ≥15 days/month in an individual with a pre-existing headache disorder, with regular overuse for >3 months of acute headache medication, including non-opioid analgesics on ≥15 days/month for ≥3 months, or any other acute medication or combination on ≥10 days/month for ≥3 months 2

The International Headache Society recommends that cranial neuralgias, central and primary facial pain, and other headache disorders be classified based on phenomenological characteristics rather than etiological causes, with a focus on specificity over sensitivity 1