Chronic paroxysmal hemicrania. X. On the autonomic involvement.

In four patients with chronic paroxysmal hemicrania, two of whom could precipitate attacks mechanically, various autonomic function tests were carried out in connection with attacks. Not all features could be studied in all patients. Forehead sweating and temperature were measured. Sweating, tearing, and nasal secretion were studied after systemic atropine administration, which reduced attack-related sweating, tearing, and nasal secretion markedly. Intra-ocular pressure was measured before and after the topical administration of an alpha-receptor blocking agent, thymoxamine. After topical thymoxamine no definite intra-ocular pressure increase occurred during precipitated attacks. In attacks precipitated by head movements, forehead sweating occurred seconds (up to 30 sec) before the pain. This study indicates that at least in some CPH cases, forehead sweating is not caused by the pain. Nor is the pain secondary to increase in intra-ocular pressure. The thymoxamine experiments seem to indicate that alpha-receptors in some way may be connected with the intra-ocular pressure increase during attack.