Diagnosis and management of nausea and vomiting in pregnancy

The aetiology of NVP is unclear, but is probably multifactorial. NVP is a diagnosis of exclusion, after other causes of nausea and vomiting have been considered and ruled out by history, physical exam and if necessary, laboratory testing. Non-pharmacological therapy, particularly lifestyles change, is widely prescribed, with limited evidence of effectiveness. Therefore, if women fail to improve, particularly if their health-related quality of life is affected, then consideration should be given to adding pharmacological therapy. Such drug therapy is based on the pathogenesis of vomiting. The choice of drug should be based first on safety data on exposure early in human pregnancy, and then demonstrated effectiveness for NVP specifically. A widely endorsed treatment algorithm begins with antihistamine therapy, followed by therapy with phenothiazines or metoclopramide, and then 5-HT3 antagonists; non-pharmacological therapy can be added at any point in time.