Indomethacin-induced de novo headache in hemicrania continua--fighting fire with fire?

INTRODUCTION: The response to indomethacin is an important feature for the diagnosis of hemicrania continua. CASE DESCRIPTION: We report the case of a 34-year-old female patient with a one-year history of strictly unilateral continuous headache with accompanying ipsilateral autonomic symptoms. As diagnostic testing was unremarkable, hemicrania continua was suspected. A dose of 150 mg of indomethacin/day reduced the headache by 80%. Although an increase to 225 mg/day led to a further reduction of headaches, a new onset of moderate to severe pulsating migrainous bilateral headache developed. DISCUSSION: As shown in older studies, indomethacin can induce de novo headaches in a presumably dose-related fashion although the exact mechanism in uncertain. A treatable secondary origin of the indomethacin-induced headaches in patients with hemicrania continua or paroxysmal hemicrania (such as reversible cerebral vasoconstriction syndrome or aseptic meningitis) should be considered and excluded by further diagnostic testing if headaches persist after discontinuation of indomethacin.