LONG-TERM EFFECT OF PROPRANOLOL THERAPY ON RENAL-FUNCTION

It has been reported that the intravenous administration of beta blocking agents reduces renal plasma flow and glomerular filtration rate from 10 to 20 per cent. In contrast, little is known about the chronic effects of these agents on renal function when given orally. To assess this question, eight normal subjects underwent timed true and regular creatinine clearances (Ccr), inulin clearances (Cin) and para-amino hippurate clearances (CPAH) after sequential weeks of therapy with 0, 80, 160, 240 and 320 mg of propranolol/day. Weight, blood pressure and heart rate were measured on each visit. Compliance was tested and confirmed by monitoring plasma propranolol concentrations. The results indicate that the use of propranolol in normal man significantly reduces Cin (27 per cent) and CPAH (26 per cent). Such decreases are probably, in part, due to reductions in cardiac output, as suggested by reductions in systolic blood pressure and heart rate. Furthermore, there was a sustained reduction in Cin following the withdrawal of propranolol therapy. Ccr technics did not reflect the magnitude of the reduction in glomerular filtration rate. The fractional excretion of creatinine demonstrated a significant inverse relationship to Cin, suggesting that creatinine secretion is increased with propranolol. We conclude that propranolol therapy results in prolonged changes in glomerular filtration rate, which may not revert to normal following its withdrawal. © 1979.