When a smoker quits, the person is left with an abnormally small number of receptor sites and a diminished supply of the natural neurotransmitters that ordinarily stimulate these receptors. This accounts for the withdrawal effects. 3-6 weeks or more with individual variations. Giving nicotine thru a patch or gum or nasal inhaler helps the body maintain the previous status quo where it relied on nicotine to stimulate the receptors. As the dose of nicotine is tapered the body slowly manufactures more receptors and more neurotransmitters and withdrawal effects begin to abate .
Smoke composition varies with the . .
Tobacco Smoke A report by Stephen Mulcahy with all the details of smoke composition.