Addiction is a term used to describe psychological dependence, obsession, or compulsion. In the medical field, addiction refers to a state in which the body relies upon a substance to function normally. When this substance is removed, it will cause a set of symptoms known as withdrawal. Addiction is often connected to increased drug tolerance, which may occur with prescribed medication as well as with substance abuse.
There is a difference between physical and psychological dependence. Physical dependence describes the need for the substance due to tolerance and to prevent withdrawal symptoms from occurring. Physical dependence occurs in drug abuse cases as well as therapeutic drug use scenarios. In psychological dependence, the subject needs the substance for psychological reasons.
Commonly, the term addiction includes psychological dependence and may refer to behaviors that are not viewed as addiction problems in the medical field. Addiction may also describe non-drug related compulsions, including gambling and computer addictions. In these cases the term is referring to an individual’s recurring compulsion to partake in an activity despite the negative or harmful consequences.