Cluster headache is a condition of extremely intense unilateral pain in the ocular or temporal region. Most patients are male. The condition occurs in clusters lasting from weeks to months. In some patients the clusters occur in seasonal periods. Prophylaxis of the bouts is based on verapamil and therapy is based on subcutaneous sumatriptan, intranasally sprayable zolmitriptan, or oxygen. In addition, corticosteroids and a short course of treatment with an ergotamine product can be used, if the bouts cannot be otherwise treated.