Addiction is a dependence on a behavior or substance that a person is powerless to stop.

The term has been partially replaced by the word dependence for substance abuse. Addiction has been extended, however, to include mood-altering behaviors or activities. Some researchers speak of two types of addictions: substance addictions (for example, alcoholism, drug abuse, and smoking); and process addictions (for example, gambling, spending, shopping, eating, and sexual activity). There is a growing recognition that many addicts, such as polydrug abusers, are addicted to more than one substance or process.

Diagnosis

In addition to a preoccupation with using and acquiring the abused substance, the diagnosis of addiction is based on five criteria:

• loss of willpower
• harmful consequences
• unmanageable lifestyle
• tolerance or escalation of use
• Withdrawal symptoms upon quitting.

Causes and symptoms
Addiction to substances results from the interaction of several factors:

• Drug chemistry
  Some substances are more addictive than others, either because they produce a rapid and intense change in mood; or because they produce painful withdrawal symptoms when stopped suddenly.
• Genetic factor
  Some people appear to be more vulnerable to addiction because their body chemistry increases their sensitivity to drugs. Some forms of substance abuse and dependence seem to run in families; and this may be the result of a genetic predisposition, environmental influences, or a combination of both.

Alternative treatment
Acupuncture and homeopathy have been used to treat withdrawal symptoms. Meditation, yoga, and reiki healing have been recommended for process addictions, however, the success of these programs has not been well documented through controlled studies.

Treatment
Treatment requires both medical and social approaches. Substance addicts may need hospital treatment to manage withdrawal symptoms. Individual or group psychotherapy is often helpful, but only after substance use has stopped. Anti-addiction medications, such as methadone and naltrexone, are also commonly used.