International Headache Society classification: new proposals about chronic headache

In the International Headache Society (IHS) classification of 1988, chronic daily headache (CDH) forms are not exhaustively categorized. The forthcoming revision of the classification will include a number of CDH forms that had been reported prior to 1988 or have been identified after that date. In particular, chronic migraine will be added to the classification as a complication of migraine, provided that use of symptomatic drugs does not exceed 10 days per month. In addition to chronic cluster headache and chronic paroxysmal hemicrania, short-lasting unilateral neuralgiform headache with conjunctival injection and tearing (SUNCT) and hemicrania continua will be comprised among CDH forms with short-lived attacks. Hypnic headache will be included in Group 4 ("Other primary headaches"). No additions will be made to the new IHS classification for forms such as new daily persistent headache (NDPH) and cervicogenic headache as proposed by Sjaastad.