The pharmacokinetics of amrinone at three dose levels in the rabbit.

Amrinone is a positive inotropic and vasodilatory compound being used to improve cardiocirculatory function in chronic cardiac failure. The linearity of the pharmacokinetics of amrinone was examined in New Zealand white rabbits given i.v. bolus doses of 1.5, 3.0, and 7.5 mg/kg amrinone. Blood samples were obtained serially for a period of 6 hours following amrinone administration. Serum concentration-time data were analyzed by nonlinear least squares regression, as well as non-compartmental techniques. There were no differences as a function of dose in the systemic clearance, elimination half-life, mean residence time, or average concentration of amrinone. The pharmacokinetics of amrinone appear to be linear in rabbits. The rabbit may be useful as an animal model to study various aspects of amrinone pharmacokinetics.