Hemicrania continua unresponsive or partially responsive to indomethacin: does it exist? A diagnostic and therapeutic dilemma

Hemicrania continua (HC) is a primary headache disorder characterized by a continuous, unilateral headache that varies in intensity, waxing and waning without disappearing completely. Ipsilateral cranial autonomic features and response to indomethacin are essential features for the diagnosis of HC. We hereby, describe three patients with the clinical phenotypes of HC in whom response to indomethacin was either incomplete or not sustained. We also review the literature especially for the presence of indomethacin response and ipsilateral cranial autonomic features.