[Studies on the pharmacokinetic equivalence of pivampicillin base and hydrochloride in capsules and tablets (author's transl)].

Absorption and urinary excretion of pivampicillin as hydrochloride and as base were studied following administration of four different formulations to 12 healthy volunteers in a cross-over study. A fluorimetric assay of ampicillin was adapted to be used with an Auto Analyzer system. The plasma concentrations observed are comparable to those reported in the literature. The amount of drug absorbed is the same for all four medications whereas absorption is more rapid from tablets than from capsules. Base and hydrochloride of pivampicillin are equivalent with respect to pharmacokinetic behaviour. So, the formulation itself seems to be more important for biological equivalence than the ionisation of the drug used in the formulation.