Metabolic effects of intravenous ritodrine infusion in pregnancy.

The effects of intravenous administration of Ritodrine on blood glucose, insulin, electrolytes, plasma and red cell potassium and venous pH were investigated. A highly significant increase in blood glucose and insulin occured. A highly significant negative correlation between serum and red cell potassium concentration was registered (r = -0.96268). No signficant changes during Ritodrine infusion were recorded in serum levels of sodium, chloride, calcium, phosphorus and magnesium. The pH did not seem to be influenced by intravenous Ritodrine administration. No cardiac arrhythmias or electrocardiographic deteriorations occurred. While intravenous Ritodrine administration seems to be safe in normal pregnancies, a risk may be present in diabetic and digitalized patients, and pregnant women being treated by diuretics.