Non-familial periodic ataxia responding to acetazolamide.

A 44-year-old man presented with symptoms of periodic ataxia, dysarthria, nausea and excessive sweating during the last twenty years. These symptoms could be provoked by physical or emotional stress and disappeared after bedrest for several hours. No other members of his family were known to have such complaints. Acetazolamide (Diamox) proved effective in preventing these symptoms. A disturbance of tryptophan metabolism is suggested as a cause of this disorder.