Drug addiction (dependence) is compulsively using a substance, despite its negative and sometimes dangerous effects.
Drug abuse is using a drug excessively, or for purposes for which it was not medically intended.
A physical dependence on a substance (needing the drug to function) is not always part of the definition of addiction. Some drugs (for example, some blood pressure medications) don’t cause addiction but do cause physical dependence. Other drugs cause addiction without physical dependence (cocaine withdrawal, for example, doesn’t have symptoms like vomiting and chills; it mainly involves depression).
Drug abuse can lead to drug dependence or addiction. People who use drugs for pain relief may become dependent, although this is rare in those who don’t have a history of addiction.
The exact cause of drug abuse and dependence is not known. However, the person’s genes, the action of the drug, peer pressure, emotional distress, anxiety, depression, and environmental stress all can be factors.
Peer pressure can lead to drug use or abuse, but at least half of those who become addicted have depression, attention deficit disorder, post-traumatic stress disorder, or another psychological problem.
Children who grow up in an environment of illicit drug use may first see their parents using drugs. This may put them at a higher risk for developing an addiction later in life for both environmental and genetic reasons.
Treatment for drug abuse or dependence begins with recognizing the problem. Though “denial” used to be considered a symptom of addiction, recent research has shown that people who are addicted have far less denial if they are treated with empathy and respect, rather than told what to do or “confronted.”
Treatment of drug dependency involves weaning off the drug gradually (detoxification), support, and stopping the drug (abstinence). People with acute intoxication or drug overdose may need emergency treatment. The treatment depends on the drug being used.