This study compares a new oral Nicotine Replacement Therapy (NRT) product containing 2 and 4 mg nicotine with Nicorette® gum 2 mg and 4 mg, after 12 hours of nicotine abstinence, with respect to nicotine pharmacokinetics, during 10 hours after start of administration. Single doses of each treatment are given once in the morning during four separate treatment visits scheduled in a crossover setting with randomized treatment sequences. The study will include 88 healthy smokers between 18-50 years, who have been smoking at least 10 cigarettes daily during at least one year preceding inclusion. Subjects and study personnel will be aware of which treatment is administered at a given visit.