Dopamine

Alcohol, nicotine, and a variety of other drugs including marijuana, cocaine, amphetamines, and heroin all appear to raise the level or the availability of dopamine in different parts of the brain. Pathways of nerve cells that produce dopamine and contain dopamine receptors are affected by all of these drugs. There is evidence that certain forms of the dopamine D4 receptor may predispose a person to drug addiction. Based on this information, researchers are attempting to develop drugs to treat addictions.