Diseases & Conditions


Drug and Substance Use and Abuse

Substance use among adolescents occurs on a spectrum from experimentation to dependence (see Drug Use and Abuse: Introduction ). The consequences range from none to life threatening, depending on the substance, the circumstances, and the frequency of use. However, even occasional use can produce significant harm, such as overdose, motor vehicle collision, and unwanted pregnancy. Although experimentation and occasional usage are common, actual drug dependence is not.

Alcohol is the substance most often used among adolescents. About 80% of high school seniors reported trying alcohol; some engage in binge drinking, which is defined as having more than 5 drinks in a row. There are risk factors for whether an adolescent will try alcohol. Genetics may be a factor; adolescents who have a family member who is an alcoholic should be made aware of the risk. Adolescents whose friends and siblings drink excessively may think this behavior is acceptable. Society and the media often model drinking as being acceptable. Despite these influences, parents can make a difference by conveying clear expectations to their adolescent regarding drinking, setting limits consistently, and monitoring the adolescent.

The majority of adults who smoke cigarettes begin smoking during adolescence. Nearly one fifth of ninth graders report smoking regularly. If an adolescent reaches the age of 18 to 19 years without becoming a smoker, it is highly unlikely that he will become a smoker as an adult. Factors that increase the likelihood of an adolescent smoking are having parents who smoke (the single most predictive factor), peers who smoke, and poor self-esteem. Using other illegal substances is also a factor. Parents can prevent their adolescent from smoking by not smoking themselves (or quitting), by openly discussing the hazards of tobacco, and by convincing adolescents who already smoke to quit and to seek medical assistance in quitting if necessary.

Use of illegal substances in adolescents, although decreasing overall in the last few years, remains high. In the year 2000, about 54% of 12th graders had used illegal drugs at some time in their life. About 62% of 12th graders reported having been drunk; 49% reported use of marijuana; 16%, amphetamines; 13%, hallucinogens; 9%, barbiturates; 9%, cocaine; and 2%, heroin. Use of methylenedioxymethamphetamine (Ecstasy), unlike the other drugs mentioned, increased dramatically in the last few years, with 11% of 12th graders reporting use at some time.

Up to 6% of boys in high school, including a number of non-athletes, have used anabolic steroids at least once. A particular problem with anabolic steroid use in adolescents is early closure of the growth plates at the ends of bones, resulting in permanent short stature. Other side effects are common to both adolescents and adults (see Other Drugs of Abuse ).

Adolescents as young as 12 to 14 years of age may be involved in substance use. Although there are risk factors for adolescents engaging in substance use, it is difficult to predict which adolescents will engage in the most serious forms of abuse. Parents should look for erratic behavior in their adolescent, mood swings, a change in friends, and declining school performance. If parents notice any of these behaviors, they should discuss their concerns with the adolescent and his doctor (see Talking With Children About Difficult Topics ).

The doctor can help assess whether an adolescent has a problem with substance use. Some parents simply bring the adolescent into a doctor demanding that he perform a urine drug test. There are a few points for a parent to keep in mind: The doctor cannot force the adolescent to take a drug test if he refuses. Results of a urine test may be falsely negative; factors influencing results are the metabolism of the drug and the time it was last used. Most importantly, in an atmosphere of accusation and confrontation, it will be difficult for the doctor to obtain a history from the adolescent, which is key to making the diagnosis.

If the doctor thinks the adolescent does have a problem, he can refer the adolescent to a professional with expertise in substance abuse; this person can make the diagnosis and determine the treatment needed. Treatment for adolescents is similar to that of adults (see Drug Use and Abuse: Introduction ) but is typically conducted in a setting with other adolescents.

Last full review/revision February 2003

Source: The Merck Manual Home Edition