The pharmacokinetics of atenolol were investigated following single intravenous (25 mg) and oral administration (100 mg) of atenolol in 13 patients with chronic liver disease and normal renal function and in 12 normal healthy volunteers. Four of the patients with chronic liver disease were not included in the statistical evaluation of kinetic data, since a reduction of creatinine clearance was observed during the course the study after ingestion of atenolol. A tendency to an increased distribution volume of atenolol could be observed in subjects with liver disease compared to normal volunteers. After intravenous and oral administration of atenolol, pharmacokinetic parameters such as elimination half-life, plasma clearance, and renal clearance did not differ significantly between patients with chronic liver disease and healthy volunteers. Thus, plasma half-life after intravenous dosing of atenolol was 6.0 +/- 0.46 hours in patients with hepatic disease and 5.0 +/- 0.4 hours in the controls, indicating absence of atenolol accumulation in hepatic failure. In the first days after starting beta-blocker therapy such as atenolol administration, parameters of kidney function as plasma creatinine, or possibly creatinine clearance, should be initially monitored at regular intervals, as there may be transient changes of renal function in patients with chronic liver disease, leading to delayed elimination of the drug.