Could a common biochemical mechanism underlie addictions?

The subject of 'drug addiction' is multifaceted and many aspects of it (eve n some of the definitions) are controversial. Collateral medical problems i nclude the spread of HIV and hepatitis C virus secondary to i.v. drug abuse and effects on prenatal brain development (1). Progress in the understandi ng of the causes of addictions and its treatment has been impeded by the la ck of a unifying biochemical theory. However, recent evidence suggests that some common mechanism might underlie addictions to otherwise apparently un related drugs. A major hypothesis has emerged suggesting that the neurotran smitter dopamine (DA) might play a central role in the molecular mechanisms of at least some addictions. If so, it would represent an important target for discovery of effective pharmacotherapy and revolutionize the pharmacis t's role in treating addictions. This short overview outlines the status of the theory of a common biochemical mechanism of drug addiction.