A novel method for using domperidone, a dopamine receptor antagonist, for treating fescue toxicosis in animals is provided. Fescue toxicosis is caused by animals grazing on endophyte-infected fescue grass. Treatment of the animal with various dosages of domperidone results in effective management of the toxin. The domperidone treatments do not cause any substantial adverse behavioral or neurological side effects in the animal. Domperidone is a more effective treatment for fescue toxicosis than previously-known agents such a metoclopramide and sulpiride
