Episodic cluster headache and narcolepsy: a case report.

A patient who first presented with episodic cluster headache later developed narcolepsy. In spite of REM sleep alterations associated with narcolepsy, the frequency and distribution of pain attacks did not change when narcolepsy occurred and were similar to those seen in cases of episodic cluster without narcolepsy. The lack of influence of narcolepsy on the pattern of cluster pains questions the role of REM sleep states in triggering pain in episodic cluster.