Intravenous propranolol administration: a method for rapidly achieving and sustaining desired plasma levels.

A model for the intravenous administration of propranolol by a bolus-infusion technique designed to rapidly produce, then maintain, predicted plasma drug concentrations was derived from elimination kinetics in single-dose studies. Prospective testing of this model in 6 adult male subjects revealed a close correlation between predicted and observed drug levels; desired plasma concentrations were achieved within 5 min and maintained over the 30-min study period. By subtracting previously given bolus doses from the dose calculated as needed to produce a desired plasma level, progressive increases in predicted propranolol levels could be effected, with apparent maintenance of equilibrium. Correlations between the bolus doses and infusion rates and the plasma drug levels were consistent and significant, and constitute nomograms from which the dose of drug required to produce a desired plasma level may be approximated. The clearance of propranolol declined slightly as the drug plasma level increased, but did not significantly affect the accuracy of the model.