Pharmacokinetics of denbufylline in healthy elderly subjects.

A single 100 mg oral dose of denbufylline was administered in an open study to ten healthy, elderly subjects in order to characterise the pharmacokinetics of parent compound and its major pharmacologically active, circulating metabolites. Plasma concentrations were determined using a combination of GC and HPLC methods. Since denbufylline plasma concentrations were close to the assay limit of reliable determination, the disposition of the compound was assessed in terms of the pharmacokinetic parameters of three active metabolites. The general pharmacokinetic behaviour of debufylline was similar to that observed in young, healthy subjects, although plasma concentrations of the metabolites were higher and half-lives tended to be longer in the elderly group. None of the subjects presented any adverse events during the study.