Cluster headache sine headache: two new cases in one family.

We report two cases of cluster headache sine headache occurring in a family of cluster headache sufferers. A 54-year-old female, suffered for 15 years from short-lasting, right-sided attacks of eye reddening, lacrimation, rhinorrea, palpebral oedema and miosis, seven to eight times per day, in periods of 20-30 days. She did not experience headache, either with or without these phenomena. Her son suffers from periorbital, short-lasting, right-sided painful attacks accompanied by eye reddening, lacrimation, rhinorrea and nasal stiffnesss, occurring in periods of 30-35 days. Soon after the end of the current cluster period he still had daily attacks lasting 10-15 min, with the oculo-nasal autonomic phenomena only. The occurrence of cluster headache sine headache and cluster headache in the same family strongly suggests that the first condition is related to the cluster headache syndrome. Cluster headache sine headache should be considered as a subtype of the cluster headache syndrome.