Nicotine

General 5: From the brain to the heart

All nicotine that enters the brain is ultimately returned to the bloodstream. The oxygen-depleted blood containing these nicotine molecules flows into increasingly larger blood vessels in the brain and is conducted back to the heart.

The heart then pumps the deoxygenated blood to the lungs, where the red blood cells can again pick up oxygen. Nicotine from a next puff on a cigarette may also enter the bloodstream at this point.

The oxygenated blood that then flows back to the heart is pumped on to the rest of the body.