This Is Your Brain

Your brain and nicotine:
The physical challenge of quitting

You smoke for many reasons. One main reason is because tobacco contains an addicting drug called nicotine. This is the substance that makes it so difficult to stop smoking, even though you want to.

Inhalation is the quickest way for a drug to reach the brain. When you smoke tobacco, high levels of nicotine enter your lungs and are quickly absorbed into your bloodstream. Nicotine reaches the brain in 7-10 seconds, stimulating feelings of pleasure and the desire for more tobacco.
Nicotine from smoking goes directly into the bloodstream from the lungs. Then the heart pumps it immediately to the brain and the rest of your body at very high concentrations. It's these high levels delivered so quickly to your brain that makes nicotine so addictive. In comparison, nicotine absorbed through the skin (from a patch) or lining of the mouth (from gum, lozenge or inhaler) enters the venous system first. Then it's pumped through both sides of the heart before reaching the brain. This takes longer, and the nicotine concentrations are lower.

"This is Your Brain" images and content courtesy of Mayo Clinic