Drug abuse (apart from general self medication, such as buying anti-malaria drugs without their being prescribed by a doctor) is mostly a covert activity. It is carried out in privacy, away from direct public gaze, or in venues where the practice is tolerated, accepted, or even positively encouraged.
Detection and recognition of drug abuse could be difficult for the untrained and uninitiated observer. They may never witness the effects of direct drug abuse and they may even easily overlook the physical and behavioral symptoms such as being due to some other caused. Perhaps only the symptoms of withdrawal may be seen, and these may be very similar to those brought about by other circumstances such as the stresses and pleasures of adolescence and therefore easily discounted. Folawiyo (1985) defines a drug as any substance other than food, which by its chemical nature, affects the structure or function of the living organism. From this perspective, the term may include any number of household, agricultural, and industrial chemicals. To a physician, a drug might be any substance used as a medicine in the treatment of physical or mental disease. When used in the context of drug abuse, the term becomes inflammatory. The meaning of drug becomes social rather than scientific. In its social sense when the term abuse is attached it takes on a negative connotation. Smith (1971) sees drug abuse as the use of any drug to the point where it interferes with the individual’s health or with his economic or social adjustment.