[HYPP: hyperkalemic periodic paralysis in the horse].

Hyperkalaemic periodic paralysis(HYPP) is characterized by intermittent episodes of muscular tremor, weakness, and collapse, and is probably caused by abnormal electrolyte transport in the muscle cell membrane. During an episode of HYPP, most animals are severely hyperkalaemic. HYPP is a hereditary disease and occurs only in American Quarter horses or crossbreds. Because these horses are now being imported into the Netherlands, HYPP should be included in the differential diagnosis of horses showing signs of muscle tremor, paresis, or paralysis. The present article reviews the literature on HYPP and describes a case showing typical signs of the disease.