Overview of Psychiatric Disorders in Children and Adolescents

ByJosephine Elia, MD, Sidney Kimmel Medical College of Thomas Jefferson University
Reviewed/Revised May 2023
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Although it is sometimes assumed that childhood and adolescence are times of carefree bliss, as many as 20% of children and adolescents have a diagnosable psychiatric disorder that causes distress and functional impairment (1). With increasing age, the prevalence of psychiatric disorders increases. All told, approximately 27.9% of US adolescents aged 13 to 17 are reported to meet criteria for 2 or more disorders (2). Studies that follow children from birth to adulthood indicate that most adult mental health disorders begin in early childhood and adolescence (3, 4). Genes associated with psychiatric disorders have been reported to show high expression throughout the lifespan, beginning in the fetus in the 2nd trimester and impacting neurodevelopmental processes, which may explain the early ages of onset (5). Most of these disorders may be viewed as exaggerations or distortions of normal behaviors and emotions.

Like adults, children and adolescents vary in temperament. Some are shy and reticent; others are socially exuberant. Some are methodical and cautious; others are impulsive and careless. Whether a child is behaving like a typical child or has a psychiatric disorder is determined by the presence of impairment and the degree of distress related to the symptoms. For example, a 12-year-old girl may be frightened by the prospect of delivering a book report in front of her class. This fear would be viewed as social anxiety disorder only if her fears were severe enough to cause significant distress and avoidance.

There is much overlap between the symptoms of many disorders and the challenging behaviors and emotions of normal children. Thus, many strategies useful for managing behavioral problems in children can also be used in children who have psychiatric disorders. Furthermore, appropriate management of childhood behavioral issues may decrease the risk of temperamentally vulnerable children developing a clinical disorder. Also, effective treatment of some disorders (eg, anxiety) during childhood may decrease the risk of a mood disorder later in life.

The most common psychiatric disorders of childhood and adolescence fall into the following categories:

Schizophrenia and related psychotic disorders are much less common.

Kids and Mental Health Part I
Kids and Mental Health Part II

Pediatric catatonia is more common than childhood schizophrenia. It may represent a psychiatric disorder but often occurs in medical conditions (eg, infections, metabolic disorders, autoimmune conditions) and frequently is not detected by pediatricians (6).

However, more often than not, children and adolescents have symptoms and problems that cut across diagnostic boundaries. For example, > 25% of children with ADHD also have an anxiety disorder, and 25% meet the criteria for a mood disorder.

Neurodevelopmental disorders affect both mental health and overall development in children. Some of these disorders include

General references

  1. 1. Merikangas KR, He JP, Burstein M, et al: Lifetime prevalence of mental disorders in US adolescents: Results from the National Comorbidity Study – Adolescent Supplement (NCS-A). J Am Acad Child Adolesc Psychiatry 49(10):980-989, 2010.

  2. 2. Kessler RC, Avenevoli S, McLaughlin KA, et al: Lifetime comorbidity of DSM-IV disorders in the National Comorbidity Survey – Replication Adolescent Supplement (NCS-A). Psychol Med 42(9)1997-2010, 2012.

  3. 3. Dalsgaard S, Thorsteinsson E, Trabjerg BB, et al: Incidence rates and cumulative incidences of the full spectrum of diagnosed mental disorders in childhood and adolescence. JAMA Psychiatry, 77(2):155-164, 2020. doi: 10.1001/jamapsychiatry.2019.3523

  4. 4. Caspi A, Houts RM, Ambler A, et al: Longitudinal assessment of mental health disorders and comorbidities across 4 decades among participants in the Dunedin birth cohort study. JAMA Netw Open 3(4):e203221, 2020.

  5. 5. Lee PH, Anttila V, Won H, et al: Genome-wide meta-analysis identifies genomic relationships, novel loci, and pleiotropic mechanisms across eight psychiatric disorders. Cell2019. doi.org/10.1101/528117

  6. 6. Dhossche DM, Wachtel LE: Catatonia is hidden in plain sight among different pediatric disorders: A review article. Pediatr Neurol 43(5):307-315, 2010. doi: 10.1016/j.pediatrneurol.2010.07.001


Evaluation of psychiatric symptoms in children and adolescents differs from that in adults in important ways:

  • Developmental context is critically important in children. Behaviors that are normal at a young age may indicate a psychiatric disorder if present at an older age.

  • Children exist in the context of a family system, and that system has a profound effect on their symptoms and behaviors; normal children living in a family in which violence and substance use disorders are present may superficially appear to have one or more psychiatric disorders.

  • Children also exist in the context of environmental stressors (eg, COVID-19 pandemic, military conflict). The resultant disruption of critical routines and isolation from extended family, peers, teachers, and cultural and religious groups have a significant impact, especially on the most vulnerable groups (1).

  • Children often do not have the cognitive and linguistic sophistication needed to accurately describe their symptoms. Thus, the clinician must rely very heavily on direct observation corroborated by observations of other people, such as parents and teachers.

In many cases, developmental and behavioral problems (eg, poor academic progress, delays in language acquisition, deficits in social skills) are difficult to distinguish from those due to a psychiatric disorder. In such cases, formal developmental and neuropsychologic testing should be part of the evaluation process.

Because of these factors, evaluation of children with a psychiatric disorder is typically more complex than that of adults. However, most cases are not severe and can be competently managed by an appropriately trained primary care practitioner. However, uncertain or severe cases are best managed in consultation with a child and adolescent psychiatrist.

Evaluation reference

  1. 1. Centers for Disease Control and Prevention: Mental Health: Stress and Coping:: Helping children cope. Updated September 23, 2022. Accessed January 5, 2023.

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