Renal haemodynamics after chronic treatment with labetalol and propranolol

1 Effective renal plasma flow (ERPF) and glomerular filtration rate (GFR) were measured in two groups of 12 patients both at rest and during sub-maximal cycloergometer exercise while on placebo and after 3 months of treatment with either labetalol or propranolol. 2 ERPF increased and renal vascular resistance decreased both at rest and during exercise after labetalol treatment, compared with placebo; the opposite was observed after propranolol treatment. 3 GFR increased after labetalol and decreased after propranolol both at rest and during exercise, compared with placebo, but these changes were not statistically significant. 4 Labetalol and propranolol resulted in the same decrease in blood pressure and a comparable incidence of side effects.