Several nicotine delivery systems have been devised to assist nicotine-dependent cigarette smokers to quit smoking. The aim of nicotine replacement therapy (NRT) is to provide temporary relief of smoking withdrawal symptoms such as irritability, anxiety, hunger, restlessness, drowsiness, and craving for cigarettes. Meanwhile, the smoker learns to resist smoking in a variety of situations that have been repeatedly associated with smoking in the past. Eventually, the goal is to relinquish the alternative source of nicotine, which is not as addictive as cigarettes. Quitting smoking, which is such a difficult task for many, is thereby simplified by breaking the process into two steps:

1. giving upthe habit of smoking while retaining some of the effects of nicotine, and
2. relinquishing the nicotine, perhaps weeks or months later.

While using an alternative nicotine delivery system, smokers also avoid the intake of hazardous...