Gelastic syncope: an unusual condition.

Gelastic syncope or laughter-induced syncope is a rare disease often misdiagnosed as narcolepsy or cataplexy. We report a 54-year-old man with syncopal episodes. Each episode started after laughter, leading to light-headedness with blurring of vision and loss of consciousness for a few seconds. The episodes resolved spontaneously. The treatment of gelastic syncope is the same as that for neurally mediated syncope.