A new preparation of nitroglycerin for uterine relaxation.

Emergent attainment of uterine relaxation is an occasional need in obstetric practice. Various agents, from amyl nitrate through volatile anesthetics have been used to relax the uterus, with varying degrees of success and side-effects. Recent publications report the use of intravenous nitroglycerin (NTG), with excellent results and few adverse side effects, but preparation for injection requires time and may produce error. We have used a new sublingual aerosol spray of NTG, at an initial dose of 0.8 mg, in 7 patients for rapid uterine relaxation and have not observed adverse side-effects. Prolonged shelf life, ready availability and ease of use make the sublingual spray attractive for urgent tocolysis.