Drug dependence (addiction) is compulsive use of a substance despite negative consequences which can be severe; drug abuse is simply excessive use of a drug or use of a drug for purposes for which it was not medically intended.
Physical dependence on a substance (needing a drug to function) is not necessary or sufficient to define addiction. There are some substances that don't cause addiction but do cause physical dependence (for example, some blood pressure medications) and substances that cause addiction but not classic physical dependence (cocaine withdrawal, for example, doesn't have symptoms like vomiting and chills; it is mainly characterized by depression).
See also
Alternative Names
Drug addiction; Addiction - drug
Causes, incidence, and risk factors
Drug abuse can lead to drug dependence or addiction. Drug dependence may also follow the use of drugs for physical pain relief, though this is rare in people without a previous history of addiction.
The exact cause of drug abuse and dependence is not known. However, the genetic make-up of the individual, the pharmacology of the particular drug, peer pressure, emotional distress,
Peer pressure may lead to use or abuse, but at least half of those who go on to addiction have depression, attention-deficit disorder, post-traumatic stress disorder or another psychological problem.
Children who grow up in an environment of
Signs of drug use in children include but are not limited to:
- A change in the child's friends, a new group
- Seclusive behavior
- Long unexplained periods away from home
- Lying
- Stealing
- Involvement with the law
- Deteriorating family relations
- Obvious intoxication (being drunk or high), delirious, incoherent, or
unconscious - Distinct changes in behavior and normal attitude
- Decreased school performance





















