TRANSDERMAL NICOTINE SUBSTITUTION - PHARMACOKINETICS OF NICOTINE AND COTININE

The use of tobacco has resulted in major health related problems world wide. Nicotine replacement is one of the most promising strategies in smoking cessation. The vivo delivery rate and the pharmacokinetic prop erties of a recently developed transdermal nicotine system (TNS) was i nvestigated in three separate studies. Two sizes (16 cm2 and 24 cm2) o f the patches were tested. Mean daily nicotine delivery, expressed by a first order kinetic, varied between 0.9 and 1.0 mg/cm2 patch. The di fferent sizes of the patches led to linearly dose-related nicotine pla sma C(max)- and AUC-values. The nicotine levels achieved were in the s ame range with those of other nicotine patches and the chewing gum. As a result of multiple dose kinetic, no significant accumulation of nic otine was observed. Mean elimination half-life of nicotine after remov al of the patches (3.5 +/- 1.8 h for the larger patch and 4.5 +/- 1.9 h for the smaller patch) was longer than reported values after i.v. ad ministration, which was reported to vary between 40 and 120 min.