[Pathomechanisms of pain attacks in Horton's headache (cluster headache)].

In view of the still unexplained pathomechanism of Horton's cluster headaches 9 patients were given a challenge test with nitroglycerin while at the same time the attacks were blocked with indomethacin. The attacks were provoked with one dose (1 mg) of nitroglycerin. Then during 3 days the patients took 75-100 mg indomethacin which dose was quite sufficient for inhibition of the activity of arachidonic acid cyclooxygenase. On the fourth day another nitroglycerine provocation was done. No inhibitory effect of indomethacin on the attack was observed. It seems doubtful that products of arachidonic acid cyclooxygenation play any role in the pathomechanism of this headache.