[Persistent vomiting].

Vomiting is a physiological reflex to protect the body from harmful influences, whereas "pathological vomiting" occurs irrespective of its primary purpose or causes secondary disturbances. Artificially induced vomiting and enemas were prophylactic and therapeutic procedures to purge the body that were employed in ancient times and reached their zenith by the end of the 18th century. The act of vomiting is regulated by the vomiting centre, where neural afferents from the chemoreceptor trigger zone, vagal and sympathetic nerve system, and from other trigger areas, are coordinated. Differential diagnosis of vomiting, emphasizing metabolic/endocrine and psychogenic vomiting--including anorexia nervosa and bulimia--are briefly discussed. Symptomatic treatment of vomiting primarily consists of the use of receptor antagonists, e.g. dopamine, histamine and 5-hydroxytryptamine-3 antagonists. Acupuncture/-pressure are also discussed as an alternative treatment method.