Nausea and Vomiting.

Nausea and vomiting are rather stereotyped symptoms. The challenge is that nausea and vomiting have many different causes and, in some patients, management may be rather complex. The clue is to determine the causal factor early. It helps to separate acute vomiting (<48 hours onset) from chronic vomiting. In acute vomiting, the causal factor or factors are most often evident. Symptomatic treatment with parenteral central-type antiemetics is the preferred treatment. Histamine-1 receptor antagonists, phenothiazines, butyrophenones, and corticosteroids are suitable drugs. For specific types of acute vomiting, for example, chemotherapy-related vomiting, the 5-HT3 receptor antagonists are costlier but effective drugs with minimal side effects. Sometimes, oral and parenteral administration of the above-mentioned drugs may be combined. The origin of chronic vomiting is often obscure, requires specialized investigation, and the causative factor may be uncorrectable. Symptomatic treatment requires a value judgement. If delayed gastric emptying is a contributing factor, prokinetic agents (metoclopramide, erythromycin, cisapride in special cases, if authorized) may prove useful. Otherwise, symptomatic treatment with central antiemetics is the only recourse. Some patients with unexplained vomiting present with psychological disturbances that act as magnifying or contributing factors and may be helped by psychotherapeutics.