Some general symptoms which may suggest a mental illness include:

In younger children

  • Changes in school performance
  • Excessive worry or anxiety
  • Frequent temper tantrums
  • Hyperactivity
  • Persistent disobedience and/or aggressive behaviour
  • Persistent nightmares
  • Poor grades, despite strong efforts

In older children and adolescents

  • Abuse of drugs and/or alcohol
  • A long-lasting negative mood, often along with a poor appetite and thoughts of death
  • Changes in school performance (e.g. falling grades)
  • Changes in sleeping and/or eating habits
  • Defying authority, missing school or truanting, stealing, or damaging property
  • Excessive complaints of physical problems (e.g. headaches, low energy levels)
  • Frequent outbursts of anger
  • Inability to cope with daily problems and activities
  • Intense fear of gaining weight

There are several different types of mental disorders which can affect children and adolescents, including:


Abuse can be physical, sexual, emotional, verbal, or a combination of any or all of these. Abuse can also be neglect, which is when parents or guardians do not take care of the basic needs of the children who depend on them. Bullying is also a form of abusive behaviour. Bullying someone through intimidation, threats, or humiliation can be just as abusive as physically beating someone.

Affective (mood) disorders:

These disorders involve persistent feelings of sadness and/or rapidly changing moods, and include depression and bipolar disorder.

Anxiety disorders:

Children or adolescents 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. These children also tend to move constantly and are impulsive (do not think before they act).

Disruptive behaviour disorders:

Children with these disorders tend to defy rules and are often disruptive in structured environments, such as school.

Eating disorders:

Eating disorders involve intense emotions and attitudes, as well as unusual behaviours associated with weight and/or food.

Elimination disorders:

These disorders affect behaviour related to using the bathroom. Enuresis, or bed-wetting, is the most common of the elimination disorders.

Intellectual disability (ID):

This disorder is characterized by below-average intelligence or mental ability and a lack of skills necessary for day-to-day living. Children/adolescents with intellectual disabilities can and do learn new skills, but they learn them at a slower pace. There are varying degrees of intellectual disability, from mild to profound.

Pervasive development disorders:

Children with these disorders are confused in their thinking and generally have problems understanding the world around them.


This disorder involves distorted perceptions and thoughts. Children as young as 6 years of age can be found to have all the symptoms of schizophrenia as their adult counterparts and to continue to have those symptoms into adulthood.

Suicidal thoughts/ attempts:

Suicidal thoughts/attempts are generally associated with depression; however, it seems to have associations with other mental disorders (E.g. Substance abuse), traumatic life events and family events, all of which may increase the risk of suicidal thoughts/attempts. Suicide and suicidal behaviour are never normal responses to stress. A suicide attempt or suicidal thoughts must always be taken seriously. Without intervention and proper treatment, a child/adolescent who has attempted suicide before or is thinking about attempting suicide, is at a greater risk of harming themselves.

Some of these disorders, such as anxiety disorders, eating disorders, mood disorders and schizophrenia, can occur in adults as well. Others begin in childhood only, although they can continue into adulthood. It is not unusual for a child to have more than one disorder.

PLEASE NOTE: The information provided on this page is not meant to replace a licensed mental health professionals diagnosis, advice and care. Please keep in mind, that just because a person displays certain symptoms of a disorder, it does not necessarily mean that the individual has the disorder. Certain symptoms can be associated with any number of disorders, therefore only a trained licensed mental health care professional can make that diagnosis and assessment. If you have any questions regarding mental health symptoms, I suggest you contact me for further clarification. Remember, the above mentioned symptoms list is strictly intended as an educational tool and its use for any other purpose is strictly prohibited. Also, keep in mind, this list is brief and does not cover every psychological disorder that is in existence; instead it focuses on the various common child and adolescent disorders and is meant to provide insight on them. Sourced from: WebMD Medical Reference