Atypical myopathy (AM) is a frequently fatal pasture myopathy that emerges in Europe. Outbreaksare of an acute and unexpected nature and practitioners and owners should be prepared to handle thecritically ill patients of this disease. Different hypotheses concerning the etiology and pathogenesishave been described. In this review, the most important hypotheses are summarized, and treatmentplans and preventive measures are suggested. At this moment, maple seeds are thought to be thecause of AM. These seeds contain a toxin, hypoglycin A, which may lead to multiple acyl-CoAdehydrogenase deficiency (MADD). Treatment is often limited to supportive care. Since treatment isoften unsuccessful, the main emphasis is currently still on prevention.