Alternating hemiplegia of childhood: case report.

We report the case of a 3 1/2 year old girl who had had attacks of alternating hemiplegia from the age of 6 months. Peculiar features from the etiopathogenetic angle seem to be the presence of a ring of mild stenosis of the vertebral artery on the right side, the influence of the upright posture on the onset of the attacks and perhaps also of variations in atmospheric pressure. The only drug that had some effect was flunarizine. Phenobartbital, haloperidol and nadolol had no appreciable effect.