Medications in pregnancy and lactation

Emergency physicians commonly prescribe medications to patients who are either pregnant or are breastfeeding. Because of the potential harm that medications may cause the fetus or the breastfed child, physicians are reluctant to prescribe a variety of medications or improperly counsel a mother to discontinue breastfeeding. This article reviews the physiology and other factors that one should consider when prescribing medications to these patients. In terms of specific medications, the authors review the Food and Drug Administration (FDA) safety categorizations for use in pregnancy, but few of the specific medications commonly prescribed for pregnant patients are included in the well-defined FDA categories. The authors also review several classes and specific medications commonly considered for use by breastfeeding patients for which the use in lactation is not well defined.