Headache occurring on 15 or more days/month in a patient with a pre-existing primary headache and developing as a consequence of regular use of ergotamine on 10 or more days/month for more than 3 months. It usually, but not invariably, resolves after the overuse is stopped.
- Headache fulfilling criteria for 8.2 Medication-overuse headache
- Regular intake of ergotamine on ≥10 days/month for >3 months.
Bioavailability of ergots is so variable that a minimum dose cannot be defined.