Pharmacokinetics and absolute bioavailability of carteolol, a new beta-adrenergic receptor blocking agent.

Abstract

The pharmacokinetics and absolute bioavailability of a new nonselective beta-adrenoreceptor blocking agent, carteolol, were investigated after administration of single intravenous and oral doses to eight normal volunteers. Plasma and urine drug concentrations were measured by an HPLC method. The pharmacokinetic parameters after intravenous dosing were obtained by a two-compartment analysis: elimination or beta-phase t1/2 4.7 +/- 0.3 h; Vc, 0.74 +/- 0.101/kg; Vd, 4.05 +/- 0.48 l/kg; Cl, 10.13 +/- 0.94 ml/min/kg; ClR, 6.56 +/- 0.58 ml/min/kg; and ClNR, 3.57 +/- 0.40 ml/min/kg. The absolute bioavailability obtained from plasma data was 83.7 +/- 8.0%, which was consistent with that derived from analysis of urine of 82.7 +/- 4.2%. The amounts excreted unchanged in urine up to 48 h after the intravenous and oral doses were 65.0 +/- 1.5% and 53.8 +/- 3.2% of the administered doses, respectively. The t1/2 for removal of the drug derived from plasma and urine findings after intravenous and oral dosing were similar, which indicates that the main route of elimination of carteolol is via the kidneys. As the ClR of carteolol exceeded the Cl of creatinine there may be renal tubular secretion of the drug.