A hypothesis for a common neurochemical basis for alcohol and drug disorders.

Research findings clearly support a uniform theory for a neurochemical basis of drug and alcohol addiction. Data are available that document final common pathways for addictive behaviors in the limbic system in which neurotransmitters modulate the drive states, mood, and instinctual behaviors. The specific areas in the brain implicated in the loss of control inherent in the addictive use of multiple drugs and alcohol are the ventral tegmentum, nucleus accumbens, locus ceruleus, dorsal raphe nuclei, and the periaquaductal grey area. These sites contain cell bodies and receptors for dopamine, norepinephrine, serotonin, and endogenous opiates respectively, where multiple drugs and alcohol can often produce their effects. The acquired drive of addiction that arises spontaneously, repetitively, and relentlessly is manifested in the addictive behaviors of preoccupation, compulsivity, and relapse to drugs and alcohol.