The pharmacokinetic parameters of apomorphine, a potent dopamine agonist, were calculated after subcutaneous and intranasal administration. Two available software packages for TDM were used (USC*PACK and MW/PHARM). The findings for the calculated parameters Kel, Vslope, Ka and bioavailability were compared. Although small, sometimes significant differences were found, the NPEM program from the USC*PACK collection provides most information about the population under investigation. We found a median Vslope of 1.7408 +/- 0.8461 (S.D.) 1/kg, and a mean Kel of 1.5341 +/- 0.3748 h-1. The absorption after intranasal administration was extremely rapid: Ka = 20.5 +/- 1.96 h-1, comparable with that found with subcutaneous absorption: Ka = 23.04 +/- 2.20 h-1.