ABSTRACT The addicted brain is physiologically and chemically distinct from the normal brain. Predisposition is fanatic thinking and neurotic need for alcohol, drugs, food etc. in defiance of negative ramifications, addiction appends development of tolerance, withdrawal symptoms, physical cravings and infatuation. Breaking the cycle of addiction means changing behaviours, which further happens in stages:pre-contemplation, contemplation, preparation, action and maintenance with a proper relapse. A large volume of published literature over the last few decades debar a comprehensive review. The addiction of the brain and its broad biological profile has attracted the attention of many researchers to explore this realm of interest. This article presents a comprehensive review of addiction pf pharmacological drugs and their effect on the human brain.