Alcohol

Because alcohol is widely available and socially acceptable, addiction may be difficult to identify. Genetic factors may have a large role in addiction to alcohol.

Tobacco

Tobacco is the most widely abused legal drug in the United States. It is extremely addictive and damaging to a person’s health.

Marijuana

Smoking marijuana damages the lungs in a similar way to tobacco. Heavy use of marijuana tends to lead to loss of energy and drive.

Cocaine

Cocaine and its derivative, crack, are potent drugs that act as stimulants and wear off quickly — eading to more use. Long-term use can cause anxiety and aggression.

Heroin

Heroin use can cause profound medical conditions such as coma, respiratory failure and shock. Use of contaminated needles can spread infectious diseases such as AIDS (acquired immunodeficiency syndrome) and hepatitis.

Signs of Drug Abuse or Addiction in Adolescents

Apart from actually seeing a teenager use drugs or come home “high,” drug abuse or addiction may be hard to recognize. A number of changes may signal trouble, such as:

• A sudden dislike of school, excuses to stay home, an unprecedented drop in grades, or dropping a school sport without explanation.
• Declining health, particularly listlessness, apathy, or a severe lack of stamina.
• A change in appearance, particularly a lack of interest in clothing and current fashion.
• Unusual demands for privacy. An adolescent may refuse to say what he or she is doing away from home or may have long unexplained stays in the bedroom or bathroom.
• Peculiar behavior. The teen may demand money, be irritable, or have unexplained displays of anger.

Excerpted from: Complete Medical Encyclopedia, American Medical Association, 2003.