Addiction is a biological, psychological and social disease. There are various factors which affect the etiology of substance abuse interacting with each other leads to the onset of consumption then addiction. The factors affecting the person, the environment and social factors are all cross-cutting factors influencing each other. Understanding all the reasons and factors of the addiction makes the trend of prevention, identification, treatment and follow up be purposefully programed.

It is a biological phenomenon that allows the organism to gradually adapt itself to some of the toxic substances and suffer the daily consumption of some of these substances which are fatal for ordinary organism.

It is a mode making a person sequentially or alternately consumes drugs. With the use of narcotic drugs, the irritability of nerve cells increase, so more medication will be needed to return it to a balanced mode (the definition of physiologists).

It is an acute or chronic intoxication which is harmful for the person and society as well resulting from using natural or chemical medications.

In academics, the term “dependency” is used.

As you know, there are three groups in the context of addiction:

1- Individuals who never use drugs.

2- Individuals who use drugs at a low or moderate level.

3- Individuals who suffer from disorders of drug consumption.

Addiction disease is in the two forms of substance abuse and dependency.

It is included to use a legal drug for once (in the case of illegal drugs, even to use a drug for once is considered abuse).

It means that although a person is not addicted to a substance, they use it; in other words, substance abuse means:

Using a substance which is illegal.

Using a substance that its consumption causes some mental changes in the person.

Using a substance that harms the person or others.

To diagnose substance abuse, at least one of the followings is required (during the last 12 months):

1- The continuity of substance abuse which would disrupt social, occupational and recreational activities (for instance absence from school or failure to do occupational responsibilities)

2- The continuity of substance abuse in dangerous situations (for instance while driving or working with mechanical tools)

3- Occurrence of repeated law violations (for example being taken to the police station)

4- The continuity of substance abuse despite the occurrence of social and inter personal problems (for example conflict between spouses)

Please note that substance abuse is a light form of dependency.

For instance:

• Opium use in Iran is illegal, so even consuming it for once is an abuse.
• The use of cannabis causes the person to lose consciousness, so it is an abuse.
• Drinking alcohol sometimes causes anger and aggression, so drinking it is an abuse.

It is a clinical syndrome with behavioral, cognitive and physiological demonstration which makes the person prefer drug consumption to other behaviors.

“Dependency” occurs as a result of repetitive consumption of addictive drugs.

In the case dependency, nerve cells get accustomed to regular exposure of drugs, and only do their duties and actions naturally when exposed to drugs.

When substance consumption is discontinued, there will appear some physical reactions called withdrawal symptoms.

Withdrawal symptoms can be very severe so that the person may relapse in order to get rid of them.

Substance makes the sense of euphoria and pleasure.

This mode can be a positive strengthener when interacting with the rewarding path in the brain.