A. Headache occurring on ≥15 days/month in a patient with a pre-existing headache disorder | |
B. Regular overuse for > 3 months of one or more drugs that can be taken for acute and/or symptomatic treatment of headache: | |
 1. Simple analgesics (paracetamol or NSAIDs) for ≥15 days/month | |
 2. Ergotamines, triptans, opioids, combination analgesics or any combination of the above mentioned ≥10 days/month | |
C. Not better accounted for by another ICHD-3 diagnosis. |