Drug rebound headache.
D000700:Analgesics / Q000009:adverse effects*; D004878:Ergotamine / Q000009:adverse effects; D006261:Headache / Q000139:chemically induced* / Q000188:drug therapy; D006801:Humans; D008881:Migraine Disorders / Q000188:drug therapy
D000700:Analgesics; D004878:Ergotamine