The term "substance addiction" is used to describe a condition where an individual is compelled to use a substance, such as drugs or alcohol, despite negative consequences. An addiction is developed when a substance is taken into the body and crosses the blood-brain barrier, altering the natural chemical behavior of the brain temporarily. The dependence is formed on the substance when more and more is needed to replicate the altered state, and the individual continues to abuse the substance despite any adverse consequences to their health, family life, work and social life.
There are certain criteria for physical dependency that is outlined in the Diagnostic and Statistical Manual of Mental Disorders. These criteria include abusing the substance by continuing to use it despite negative consequences, tolerance, and withdrawal. Physical dependence on a substance is defined by withdrawal symptoms that surface when the substance is suddenly stopped and no longer in the body. Certain drugs such as opiates, benzodiazepine, barbituates and alcohol induce physical dependence and once this dependence is in place discontinuing their use without medical assistance can be deadly. Once a person's body is biologically dependent on the substance, it responds by becoming quite ill if the body does not receive that substance. When this happens, the person is said to be physiologically dependent on the substance. This has also been said to be true with process or behavior dependency as well as addictive substances.
Psychological dependence is a dependency of the mind and can produce psychological withdrawal symptoms such as cravings. A psychological dependence is formed when a substance is used to alter mood and create feelings of happiness, self-confidence, or just better in some way. In order to keep experiencing these "high" feelings, an individual is compelled to continue to use the substance that gave them these feelings. In this case, a person is said to be psychologically dependent. Addictions typically involve both physiological and psychological dependency, irritability, insomnia, and depression.
The causes of addiction are complex and largely still unknown. Doctors have been working to understand possible causes and connections for many years. At one time the popular theory was that addiction was a moral weakness or matter of will power. This theory is no longer accepted by medical professionals. It is unknown why one person becomes an addict or alcoholic while another does not. Some factors that contribute to addiction may include:
Family history of abuse
Genetic predisposition to addiction
Use of illegal substances by family members and friends
Brain deficiencies such as fewer natural opiates or fewer receptor sites
Inability to self-soothe or self-regulate mood
Use of illegal substances by family and friends
Family system where love, warmth, praise, and acceptance are lacking
Poor coping skills
Poverty, poor living conditions, or isolation from other people
Failure in school, work and relationships
Peer pressure or growing up in a neighborhood in which drug use is common
Medical use of prescription drugs for legitimate reasons
Addictions grow stronger over time for two reasons
People can also become psychologically addicted to substances and activities. All forms of addictions, whether to a substance or an activity, have some common symptoms, including:
Loss of control: Addicts are unable to control their actions or their continued use of a substance. Their lives become unmanageable. They may decide to stop using a substance one day and then begin using it again the next. Many addicts try using a different substance, try using it at a different time during the day, try to control their use harder etc.
Tolerance: Tolerance occurs when an individual needs more the substance at a higher dosage or more substances over time. For example, early in an addiction, a person may need only a certain amount of alcohol to feel "good," as the dependency grows they need more and more alcohol to get the same response. Reverse tolerance is a condition that occurs in late stage alcoholics where the reverse begins to happen and a small amount of alcohol makes them intoxicated. In most cases the brain has suffered damage at that point.
Withdrawal: Refers to the symptoms that appear when a drug that is depended upon is suddenly stopped or decreased in dosage. The body begins to become ill and suffer in adverse ways from the biochemical changes occurring due to the drug that is depends on being discontinued. Withdrawal symptoms can be physical such as shaking, trembling, hallucinating, throwing up, feeling physical pain or psychological as would be the case in feeling angry, irritable, and craving. Addicts can enter a center for substance abuse treatment or a drug detox center for help with the detox process.
Impairment: An individual's judgment becomes impaired after continued use of a substance that they depend on. They begin to make choices to use under conditions they never would have considered in the past pre-using. For example, driving a car while drunk when they vowed this is something they would never do. The mere act of continuing to use a substance even though the use is causing negative consequences is proof of impaired judgment. Denial, minimizing, rationalizing and becoming defensive are key components in impairment.