Oral bioavailability and intravenous pharmacokinetics of amrinone in humans

Fourteen healthy males received two 75-mg doses of amrinone as a single capsule and as an intravenous solution in a single-dose crossover study. The mean (+/-SD) bioavailability, based on the area under the plasma concentration versus time curves, was 0.93 +/- 0.12. The plasma data for these subjects during the intravenous phase was described by an open two-compartment body model with a mean (+/-SD) apparent first-order terminal elimination rate constant, beta, of 0.19 +/- 0.06 hr-1, which corresponds to a half-life of 3.6 hr.