As defined by Jaffe (1980), drug addiction is "a behavioral pattern of drug use, characterized by overwhelming involvement with the use of a drug (compulsive use), the securing of its supply and a high tendency to relapse after withdrawal. In addition, it is characterized by craving, withdrawal and tolerance." Traditionally, the concept of addiction only applied to substance abuse. In recent years, the concept of addiction is not only a biological concept that is precipitated from substance abuse, but it also considers cultural, social, and cognitive or psychological influences. Addiction is best understood as an individual's adjustment to his or her environment that is often self-destructive. It represents a pattern of coping through habituation. Rather than being a distinct disease entity, it is thought of more as a continuum of feeling and behavior.

There are three ways that drug addiction can be recognized in an individual.

  1. The addicted person exhibits a heightened need for a substance. This need then leads to habits that are aimed at acquiring the substance.
  2. Upon discontinued use of the abused substance, the individual suffers intensely.
  3. The hallmark of addiction is the addicted individual's willingness to sacrifice everything, to the point of self-destruction, to take the drug.
These signs are based in the biology of addiction, and therefore can be applied more appropriately to drug addiction than to addictions of other types. However, even drug addiction is not solely based on physiology. Rather, the feeling of craving and withdrawal from a drug, an object, or a behavior engages an individual's expectations, values, and self-image for gratification. The concept of addiction provides a powerful description of human behavior that involves compulsion and self-destruction.

There are a range of factors that influence an individual's reaction to drugs and susceptibility to addiction. Cultural and historical variations are among the most potent. These concepts are deeply rooted in society and begin influencing individuals at a very young age. By the time of maturity, when impressions are solidified, the cultural and historical perspectives of addiction are difficult to cast off. One may question why these prejudices persist through generations. Some explanatory factors are that harboring of popular prejudices is an accepted norm, that deficiencies in research strategies are poorly acknowledged, and that the legality of various substances are unsettled. Ultimately, however, theories of addiction need to include not just the biological perspective, but also the subjective perceptions, cultural, historical and individual, that comprise the complex behavior known as addiction.