A preliminary study on the interaction between ethanol and propranolol in normal human subjects.

Ethanol significantly increased the steady-state peak concentration of propranolol while propranolol significantly reduced the total body clearance of ethanol in healthy human volunteers. Ethanol per se caused tachycardia and rise in systolic blood pressure while propranolol administration resulted in bradycardia. In combinations, ethanol and propranolol caused significant fall in diastolic blood pressure without any significant changes in the heart rate and systolic blood pressure compared to the control readings of four healthy male volunteers. The kinetic and haemodynamic interactions observed between ethanol and propranolol in the preliminary study are of clinical relevance and need further exploration.