Headache occurring on 15 or more days per month for more than three months, which, on at least 8 days per month, has the features of migraine headache.
Diagnostic criteria:
A. Headache (tension-type-like and/or migraine-like) on ≥15 days per month for >3 months and fulfilling criteria B and C
B. Occurring in a patient who has had at least five attacks fulfilling criteria for Migraine without aura and/or criteria for Migraine with aura
C. On ≥8 days per month for >3 months, fulfilling any of the following:
- criteria Migraine without aura
- criteria Migraine with aura
- believed by the patient to be migraine at onset and relieved by a triptan or ergot derivative
Source
Headache Classification Committee of the International Headache Society (IHS) (2013). The International Classification of Headache Disorders, 3rd edition (beta version). Cephalalgia 2013; 33: 9-807.