Types of Common Mental Illness

For further information on risk factors signs and symptoms associated with common mental health see: beyondblue support service

It is important to have an understanding of what mental health is and how it may affect individuals so to be more effective when responding to issues that may arise.

Presentations that are important to be aware of include depressionanxiety and substance use:


  • Depression is one of the most common mental health problems, affecting approximately 4% of the Australian population.
  • Although it may be typical for some people to report feeling 'depressed,' 'down' or 'blue' on occasions this may not reflect clinical depression. Clinical depression is indicated by a persistent low mood (for more than two weeks), a loss of interest in daily life, which notably impacts on the person's ability to function.
  • In some cases there may not be a clear reason for the person's depressed mood. Quite often depression does not develop from one single event, but rather an accumulation of events or factors.

Indicators that a candidate may be experiencing depression include:

  • Difficulty concentrating or 'staying on task'
  • Turning up late for meetings and other commitments
  • Looking tired and fatigued or with less care for personal presentation and hygiene
  • Easily angered or frustrated with tasks or other people
  • Avoiding being with other people or withdrawing socially
  • Finding it difficult to meet reasonable deadlines
  • Difficulty accepting constructive and well delivered feedback
  • Difficulty managing multiple tasks or demands
  • Making statements about their sense of worthlessness ("I am useless," "I can't do it," "I am failure").
  • Unexplained absences
  • Increased use of alcohol to cope with other symptoms of depression
  • Sometimes substance use (PDF 919.0 KB) may be a trigger for symptoms of other mental health illness. For example, if a person has a predisposition to a psychotic illness, drug use may trigger a psychotic episode.
  • Conversely, for other people, having a mental illness such as depression or anxiety may make them more likely to use drugs and alcohol. Drug use or 'self-medicating' can alleviate the experience of some symptoms in the short term. However, over time, substance use can increase symptoms severity and led to the development of addition symptoms – ultimately prolonging the illness.
  • Substance use can increase the risk for someone with a mental illness. Drugs and alcohol can lower inhibitions and therefor increase the likelihood that the person will act in extreme ways to how they are feeling. This could include acting on suicidal ideation or getting into unsafe situations.

Substance Use Disorders

Any type of substance use, including alcohol, illegal drugs and prescription medications, can be a problem if it:

  1. Changes the way a person acts (e.g. less motivated, anxious, irritable, aggressive);
  2. Impacts on their way of life (e.g. not getting on with people, difficulties functioning at work or study, trouble with the law, financial issues due to increased spend on substances); and
  3. Changes the person's appearance (e.g. changes in weight, poor self-care, appearing intoxicated).