Pharmacokinetics of nicotine after application of a 30 cm2 nicotine patch under steady-state conditions.

Transdermal nicotine systems (Nicotinell 30) were applied daily to the skin of healthy nicotine-dependent smokers for 4 days. Blood samples were taken for the measurement of nicotine and cotinine in plasma using capillary gas chromatography with nitrogen detection. The plasma concentration-time profiles of nicotine and cotinine and the pharmacokinetic parameters cmax, tmax, AUC and the elimination half-life were determined under steady-state conditions. Nicotine levels after application of the 30 cm2 patch were in accord with published values for 10, 20 and 2 x 20 cm2 patches. The elimination half-life of nicotine after removal of the patch was longer than reported values obtained after i.v. application.