Nicorette nicotine patch held in a woman's hand. This is a type of nicotine replacement therapy (NRT). Nicotine is an addictive drug found in cigarettes. When the patch is applied to the surface of the skin, the nicotine in the patch is released in small measured doses into the bloodstream. A course of patches slowly decreases the amount of nicotine delivered, easing the withdrawal symptoms felt by smokers who are trying to quit.