The Initial Examination of the Efficacy of Low-Dose Promethazine for the Treatment of Nausea and Vomiting in the Hospitalized Elderly

The purpose of this study was to assess efficacy and safety of 3 doses (6.25 mg, 12.5 mg, 25 mg) of intravenous (IV) promethazine in treatment of established nausea and vomiting (N/V) in hospitalized elderly patients. Study participants aged ≥65 years received at least 1 dose of IV promethazine for treatment of N/V. Outcomes were degree of efficacy and safety. Efficacy was measured by time to relief and whether relief occurred. Safety was measured by the incidence of adverse drug reactions (ADRs). The results showed no difference in the time to relief and proportion of patients who felt relief between the 6.25-mg and 12.5-mg groups. The median frequency of ADRs in the 6.25-mg group, based on total administrations, was significantly less than the 12.5-mg group (P = .048). This study suggests a starting dose of 6.25 mg IV promethazine is as effective as higher doses and has fewer ADRs.