Among the comorbid psychiatric conditions, disruptive behavior disorder is common which includes conduct disorder, oppositional defiant disorder, and attention deficit hyperactivity disorder (Bukstein et al. 1989). In the MECA study, 32 % adolescent reported current mood and 20 % reported having comorbid anxiety symptoms (Kandel et al. 1982). Eating disorders are another type of psychiatric disorder often associated with adolescent substance abuse. Studies point to a high incidence of substance abuse among bulimic patients as opposed to anorexia nervosa.

The purpose of epidemiology, broadly stated, is the “study of the distribution and determinants of health related states of events in specified populations, and the application of this study to control of health problems”. When this definition has been applied to drug use and drug use disorders, epidemiology has historically served as a foundation for understanding the nature and extent of drug use, abuse, and dependence in the population, for informing basic, clinical, treatment, and services research, and for developing prevention strategies.

Estimates of “Illicit drug use” reported from NSDUH showed that in 2006, an estimated 20.4 million Americans aged 12 or older were current (past month) illicit drug users. Marijuana was the most commonly used illicit drug (14.8 millions past month users). In 2006, marijuana was used by 72.8 % of current illicit drug users and was the only drug used by 52.8 % of them. An estimated 5.2 million persons were current nonmedical users of prescription pain relievers in 2006, which is more than the estimated 4.7 million in 2005. There were 2.4 million current cocaine users, the same as in 2005 (2.4 millions). The number of current heroin users increased from 136,000 in 2005 to 338,000 in 2006, and the corresponding prevalence rate increased from 0.06 to 0.14 %. Hallucinogens were used in the past month by 1.0 millions persons (0.4 %) in 2006.

Among youths aged 12 to 17 years of age, 9.8 % were current illicit drug users: 6.7 % used marijuana, 3.3 % engaged in nonmedical use of prescription-type drugs, 1.3 % used inhalants, 0.7 % used hallucinogens, and 0.4 % used cocaine. As in prior years, males were more likely than females among persons aged 12 or older to be current illicit drug users in 2006 (10.5 vs. 6.2 %, respectively). Among youths aged 12–17, the types of drugs used in the past month varied by age group. Among 12- or 13-year-olds, 2.0 % used prescription-type drugs nonmedically, 1.2 % used inhalants, and 0.9 % used marijuana. Among 14- or 15-year-olds, marijuana was the dominant drug used (5.8 %), followed by prescription-type drugs used nonmedically (3.1 %), and then by inhalants (1.7 %).

Prevalence rates among 12- to 17-year-olds were lower in 2006 than in 2002 for current use of illicit drugs other than marijuana; nonmedical use of psychotherapeutics, pain relievers, and tranquilizers; and use of hallucinogens, LSD, and ecstasy. The rate for illicit drugs other than marijuana declined from 5.7 % in 2002 to 4.9 % in 2006, nonmedical use of psychotherapeutic drugs decreased from 4.0 to 3.3 %; nonmedical use of pain relievers declined from 3.2 to 2.7 %; and nonmedical use of tranquilizers decreased from 0.8 to 0.5 %. Adolescents’ current use of hallucinogens declined from 1.0 % in 2002 to 0.7 % in 2006, reflecting decreases in current use of ecstasy (from 0.5 to 0.3 %) and LSD (from 0.2 to 0.1 %).

The 32nd Annual Monitoring the Future survey of 50,000 8th, 10th, and 12th graders in more than 400 schools nationwide which is the percentage of US adolescents who use illicit drugs or drink alcohol have showed a decade-long drop in 2006. This year’s survey reveals that a fifth (21 %) of today’s 8th graders, over a third (36 %) of 10th graders, and about half (48 %) of all 12th graders have ever taken any illicit drug during their lifetime.

The proportion saying they used any illicit drug in the prior 12 months continued to decline in 2006, and the rates (15, 29, and 37 % in 8th, 10th, and 12th grades, respectively) are now down from recent peak levels in the mid-1990s by about one-third in 8th grade, one quarter in 10th grade, and one-eighth in 12th grade.

The magnitude and dynamics of drug abuse at the national level have not been well researched in India. This deficiency of data is contributed by the lack of awareness on the one hand and the sheer vastness of the country on the other. “The extent, pattern and trends of drug abuse in India- National Household Survey” attempts to minimize the potential error of any single technique and provide a comprehensive picture depicting the data obtained from various components of the national survey Ray and Mandal (2004).

Information on drug abuse among youth is available from the following: (a) National Household Survey (NHS); (b) Rapid Assessment Survey (RAS); and (c) Drug Abuse Monitoring System (DAMS). The data from NHS revealed that among current alcohol, cannabis, and opiates users, about 21 and 0.1 %, respectively, were below 18 years. The mean age of onset of various drugs was during youth, between 21 and 23 years.

Among treatment seekers, there were a few young subjects (below 15 years and between 16 and 20 years) being reported from the DAMS component. Overall, 0.4 and 4.6 % of total treatment seekers in various states belonged to the above age groups, respectively. Among users of heroin, cannabis, and propoxyphene, 0.5–0.8 % were in the group below 15 years. The proportion of opium and alcohol users in this age group was considerably low. The proportion of users of various drugs belonging to the age group 16–20 years varied between 2.7 and 18.8 %, the percentage of users of propoxyphene being the highest. It was noted that young people reporting to treatment were more often users of propoxyphene, heroin, and cannabis.

Some information on drug abuse by youth is also available from the data obtained from NGO (Children) and NYKs who participated in the DAMS component. Profile of drug users shows that alcohol was the commonest drug of abuse followed by cannabis and opiates. About 25 % reported use of “other drugs”, i.e., mostly tobacco products. The proportion of alcohol users was higher among subjects from NYKs. Most were introduced to drugs at young age (below 15 years). Some information on drug abuse by young and very young subjects is available from the data from the Rapid Assessment Survey (RAS). A total of 368 out of 2,831 subjects were below the age of 20 years. It clearly showed that street children use a variety of substance including inhalants, cannabis, alcohol, and heroin. Some of these children were involved in drug dealing.

The clinical trials for adolescent substance abuse treatment that were reviewed provide support for the benefits of cognitive–behavioral interventions. Consistent with literature reviews (Catalano et al. 1990–1991; Weinberg et al. 1998), these results show that outpatient CBT treatment can be effective in reducing adolescent substance use and related problems. However, some variation in outcomes was observed. For example, while Liddle et al. (2001) and Waldron et al. (2001) both found greater evidence for the immediate benefits of family therapy, they also found marked substance use reductions, although delayed, for the cognitive–behavioral group interventions. However, Dennis et al. (2004) did not find evidence that family-based treatments had superior outcomes. Both group and individual CBT outcomes were as favorable as those of the family interventions and were significantly more cost-effective. Similarly, Kaminer et al. (1998a, b) found consistent evidence for the efficacy of group CBT interventions. Overall, the outcomes appear better (Simpson et al. 1987; Hubbard et al. 1985). The empirical support for the efficacy of CBT with adolescents is also similar to evidence found for treatment studies for adult drinking and drug use (Woody et al. 1993; Graham et al. 1996; Marques and Formigoni 2001). The results of these recent clinical trials for adolescents are particularly important because of their enhanced design and methodological features that represent significant improvements over previous studies.

By contrast, research evaluating CBT for other behavioral problems and disorders associated with adolescent substance abuse, such as conduct problems (Kendall et al. 1990; Kazdin 1995), depression (Clarke et al. 1992; Wood et al. 1996; Birmaher et al. 2000) and anxiety (Barrett et al. 2001) for adult substance abuse and dependence, and behavioral approaches for preventing substance use in high-risk youths (Botvin and Botvin 1992) is well established. Given the success of CBT for other populations, especially for adolescents diagnosed with disorders known to co-occur with substance abuse, the newly emerging support for CBT with substance-abusing youths represents significant progress in the field.

At present, several evidence-based, developmentally sensitive approaches are emerging for addressing alcohol, nicotine, and other drug use problems among adolescents (Wagner and Waldron 2001). These include family systems approaches (Liddle and Hogue 2001; Waldron 1997), brief motivational interventions, guided personal change programs, cognitive–behavioral skill-building treatments, and assertive aftercare programs (see Box-16.1). Moreover, there has been increasing attention devoted to community-based treatment models (e.g., treatment provided in neighborhood clinics, schools, and/or the home), which have greater ecological validity and impact, and fewer barriers to treatment access than more traditional treatment models for adolescent substance abuse. Finally, given the high rates of psychiatric comorbidity among adolescents with alcohol or other drug problems, an effective treatment “package” for substance-abusing teenagers may include medication. Group therapy and 12-step programs are commonly used with adolescents, but recent reports suggest that these interventions should be approached with caution.

History taking is an important part of assessment procedure. The patients with substance use disorders may not easily give a reliable report about their substance use. It should not be surprising that these patients will attempt to protect their ability to continue to use by minimizing, denying, or even lying about the extent of use and the problems resulting from it. While eliciting the history, the clinician should be alert to these characteristic defenses and should have a nonjudgmental attitude toward the patient. The patients should be encouraged to share the information without any hesitation. Sometimes, the patient’s reluctance to disclose sensitive information can be lessened by a frank discussion about how this information will be used and assuring about the confidentiality.

A detailed physical and mental status examination is required. Physical examination is essential because of the wide range of medical disorders associated with tobacco, alcohol, or other drug use. The clinician should refer the patient to primary care or internal medicine physicians for a complete physical examination.

A detailed mental status examination, including assessment of cognitive functioning, is required for the accurate diagnosis of substance dependence, comorbid psychiatric disorders, and cognitive dysfunction. Assessment of cognitive function should include evaluation of attention and concentration, recent and remote memory, perception, abstract reasoning, and problem-solving ability.

The objective assessment can be grouped in 3 main categories: (1) self-report measures/structured semi-structured interviews, (2) direct behavioral observation, and (3) physiological measures.