Types of Mental Illnesses


This factsheet created by Reach Out.com

Provided by Reach Out

We have partnered with Reach Out to bring you the best factsheet information we can on this topic. Reach Out offers information, support and resources to help young people improve their understanding of mental health issues, develop resilience, and increase their coping skills and help-seeking behaviour.

What is a mental health difficulty?

Mental health difficulties cause people to think, act, and feel differently from how they usually do. This may be different to how the people around them think and act but for the person with the mental health difficulty these feelings are real. Having a mental health difficulty does not make someone lazy, bad or stupid.

Mental health difficulties are common with at least 1 in 5 people experiencing one. Some are more severe than others, and some will have more noticeable symptoms. In most cases they are manageable and people are able to live happy and successful lives.Credit User - Zoe Favole @ Flickr http://www.flickr.com/photos/zoefavole/3092718742/

What causes mental health difficulties?

Mental health difficulties can affect a person from any religion, culture, economic background or nationality. There are a number of factors that are associated with mental health difficulties.

Some of these factors may include:

  • Family history

    Most illnesses have a genetic component. This means that if a family member has a mental health difficulty, others may be at higher risk.

  • Chemical balance

    An imbalance of chemicals (called neurotransmitters) in the brain can cause symptoms of a mental illness to emerge. Most drugs used to manage mental health difficulties try to correct this balance.

  • Stressful life events

    Stressful experiences such as grief or loss, experiencing violence or a traumatic accident may trigger mental health difficulties.

  • Drug use

    Research has shown that using drugs may lead to mental health difficulties. For example, there has been a link between psychosis and the heavy use of marijuana and amphetamines.

Types of Mental illnesses

There are many terms used to describe mental health difficulties. Below is an explanation of some of the common terms used.


When someone feels sad and down for a period of time that is longer than a couple of weeks they may be depressed. People experiencing depression may experience some or all of the things below:

  • feelings of hopelessness or helplessness
  • loss of interest in what they usually enjoy
  • a lack of energy
  • changes in sleeping and eating patterns
  • crying a lot for no reason
  • feeling anxious

If someone is experiencing one or a number of these things, seeking help is important. Your local doctor is a good first step and they may refer you to a psychiatrist or help you themselves. A psychologist is also a specialist who can help you work through depression.  Reach Out's Who can help you section has more information on the different people who can help.


If someone becomes very confused and appears out of touch with everyone else's perception of the world, they may be experiencing a psychotic episode.

When someone is experiencing a psychosis they may:

  • have hallucinations
  • hear voices that may not be heard by anyone else
  • have false beliefs known as delusions
  • experience paranoia
  • have strange and disorganised thinking
  • have strange and disorganised behaviour
  • have difficulty speaking coherently
  • may appear quite flat

Some drugs such as hallucinogens, marijuana, and amphetamines may trigger a psychotic episode.

Treatment of psychosis usually involves medication, and if someone is experiencing a psychotic episode, it is important that they seek help from a doctor, psychiatrist or a clinical psychologist. Friends and family can also provide support. Achieving stability after a psychotic episode may take some time. Check out Reach Out's Who can help you section for more information on psychologists, doctors and psychiatrists.


Schizophrenia is a type of psychosis. Those who experience schizophrenia may have:

  • confused speech patterns
  • Ongoing delusions - believing things about themselves that no one else believes, such as thinking they are being watched, or have particular powers or abilities they don't actually have.

Schizophrenia does not mean someone has more than one personality or 'split personalities'. With medication and support, schizophrenia can be managed. Having the support of family and friends may also be very helpful. The earlier people receive help for schizophrenia, the greater the chance of a better outcome.

Treatment of Mental Illness - The Merck Manuals

Understanding what causes some mental health disorders helps doctors tailor ...
doctors and other types of doctors also prescribe drugs to treat mental health ...


There are many forms of anxiety disorders that can stop people from doing what they want to do. Some people have sudden unexplained panic attacks that can seem out of their control. Some people experience phobias like agoraphobia (fear of being in an open space). Other people become anxious about something in particular. This can lead to obsessive behaviour causing them to check and recheck things, for example: having to go home to check that they turned off the stove.

People who experience high levels of anxiety can learn to manage and reduce their anxiety levels. A form of therapy called cognitive behavioural therapy has been shown to be really effective in managing anxiety. Check out our section on Anxiety fact sheet for more information.

Attention Deficit Disorder

When someone has problems concentrating and staying focused on tasks, they may have an attention deficit disorder. The condition may have started in early childhood. They may be easily distracted, excessively active, or have a tendency to go off into daydreams more than others.

People with attention deficit disorders find situations like paying attention in class particularly difficult, and this can lead to conflict with teachers or other authority figures. They may feel like the world is against them because of the conflicts that arise due to their inability to concentrate.

People with attention deficit disorders may have a lot of energy and become involved in many activities that can be positive. Young people experiencing attention deficit disorder may need to be helped by their family and school, as well as receiving good medical support. After proper medical assessment, medication may be helpful in managing symptoms.

Eating disorders

Eating disorder is the term used to describe a group of illnesses where someone has a distorted view of body image with a preoccupation over eating, food and weight. There are a number of different eating disorders including Anorexia nervosa, Bulimia nervosa, and Binge eating disorder. Visit our eating disorders section to find our more.

If someone has an eating disorder, it is a good idea for people to get help as soon as possible. This help may come from their local doctor who may then refer them to a psychiatrist or other mental health professional.



Worksheets, learning packs and SATs papers for TheSchoolRun members

Worksheets, learning packs and SATs papers for TheSchoolRun members Welcome to the Members’ area Hello! Subscribing to TheSchoolRun is one of the best things you can do for your child's education - and at only £1.


TransGriot Note: Guest post from Dainna Cicotello.   She's an author, lecturer and one of our trans community builders and leaders in Colorado and nationally who mentored me and many of my generation of trans leaders.