Nearly 5 million children in the U.S. have some type of serious mental illness (one that significantly interferes with daily life). In any given year, 20% of American children will be diagnosed with a mental illness.
The term "mental illness" is not entirely accurate, because there are many "physical" factors -- including heredity and brain chemistry -- that might be involved in the development of a mental disorder. As such, many mental disorders can be effectively treated with medication, psychotherapy (a type of counseling), or a combination of both.
Identifying mental disorders in children can be tricky for health care providers. Children differ from adults in that they experience many physical, mental, and emotional changes as they progress through their natural growth and development. They also are in the process of learning how to cope with, adapt, and relate to others and the world around them.
Furthermore, each child matures at his or her own pace, and what is considered "normal" in children falls within a wide range of behavior and abilities. For these reasons, any diagnosis of a mental disorder must consider how well a child functions at home, within the family, at school, and with peers, as well as the child's age and symptoms.
Which Mental Health Conditions Are Most Common in Children?
There are several different types of mental disorders that can affect children and adolescents, including:
Anxiety disorders: Children with anxiety disorders respond to certain things or situations with fear and dread, as well as with physical signs of anxiety (nervousness), such as a rapid heartbeat and sweating.
Attention-deficit/hyperactivity disorder (ADHD): Children with ADHD generally have problems paying attention or concentrating, can't seem to follow directions, and are easily bored and/or frustrated with tasks. They also tend to move constantly and are impulsive (do not think before they act).
Disruptive behavior disorders: Children with these disorders tend to defy rules and often are disruptive in structured environments, such as school.
Pervasive development disorders: Children with these disorders are confused in their thinking and generally have problems understanding the world around them.
Eating disorders: Eating disorders involve intense emotions and attitudes, as well as unusual behaviors associated with weight and/or food.
Elimination disorders: Disorders that affect behavior related to using the bathroom. Enuresis, or bed-wetting, is the most common of the elimination disorders.
Learning and communication disorders: Children with these disorders have problems storing and processing information, as well as relating their thoughts and ideas.
Affective (mood) disorders: These disorders involve persistent feelings of sadness and/or rapidly changing moods, and include depression and bipolar disorder.
Schizophrenia: This disorder involves distorted perceptions and thoughts.
Tic disorders: These disorders cause a person to perform repeated, sudden, involuntary (not done on purpose), and often meaningless movements and sounds, called tics.
Some of these disorders, such as anxiety disorders, eating disorders, mood disorders and schizophrenia, can occur in adults as well as children. Others begin in childhood only, although they can continue into adulthood. It is not unusual for a child to have more than one disorder.
Article Source: http://www.webmd.com/mental-health/mental-illness-children