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Depression is more than just a low mood – it’s a serious medical condition that affects your physical and mental health.


You may have been depressed if for more than two weeks, you’ve felt sad, down or miserable most of the time, have lost interest or pleasure in usual activities, or if you’ve experienced several of the signs and symptoms in at least three of the categories below.

  • Behavioural changes including withdrawing from family and friends, an inability to concentrate or get things done, and increased reliance on alcohol and sedatives
  • Feelings of unhappiness, irritability, indecision and guilt, a sense of being overwhelmed or losing confidence
  • Thoughts such as “I’m a failure”, “It’s all my fault”, “I’m worthless”, or believing people would be better off without you
  • Physical symptoms such as being tired all the time, feeling sick or rundown, rapid weight loss or gain, appetite changes, sleep problems or a churning gut.

It’s important to remember that we all experience some of these symptoms from time to time. That needn’t mean you’re depressed. And not everyone who is experiencing depression will have all these symptoms.


The causes of depression are not fully understood, but we do know that a combination of psychological, social, genetic and biological factors can contribute to its development. Depression usually results from a combination of recent events and other longer-term or personal factors, rather than one immediate issue or event.

  • Life events Continuing difficulties – long-term unemployment, living in an abusive or uncaring relationship, long-term isolation or loneliness, or prolonged work stress – are more likely to cause depression than recent life stresses. However, recent events can ‘trigger’ depression if you’re already at risk.
  • Family history Depression can run in families and some people will be at an increased genetic risk. However, having a parent or close relative with depression doesn’t mean you’ll automatically have the same experience.
  • Hormones Changes during pregnancy, after you have a baby, during menopause and if you have thyroid problems can cause depression.
  • Personality Some personality types are more at risk, particularly people who tend to worry a lot, have low self-esteem, are perfectionists, are sensitive to personal criticism, or are self-critical and negative.
  • Serious medical illness The stress and worry of coping with a serious illness can lead to depression, especially if you’re dealing with long-term management and/or chronic pain.
  • Drug and alcohol use Drug and alcohol use can both lead to and result from depression. Over 500,000 Australians will experience depression and a substance use disorder at the same time, at some point in their lives.
  • Changes in the brain — some people with depression have been shown to have abnormal levels of neurotransmitters (brain chemicals) such as serotonin, noradrenaline and dopamine. Antidepressants that change these levels can be effective in treating some people with depression.

Types of Depression:

There are different types of depressive disorders. Symptoms can range from relatively minor (but still disabling) through to very severe.

Major depression

Sometimes called major depressive disorder, clinical depression, unipolar depression or simply ‘depression’. It involves low mood and/or loss of interest and pleasure in usual activities, and other symptoms. Symptoms are experienced most days and last for at least two weeks, and interfere with all areas of life, including work and social relationships. 


A severe form of depression where many of the physical symptoms of depression are present. The person starts to move more slowly and is more likely to have a depressed mood that is characterised by complete loss of pleasure in almost everything.

Psychotic depression

People with depression sometimes lose touch with reality and experience psychosis. This can involve hallucinations (seeing or hearing things that aren’t there); delusions (false beliefs that aren’t shared by others); or paranoia (such as feeling everyone is against them).

Antenatal and postnatal depression

Almost 10 per cent of women will experience depression during pregnancy (the antenatal or prenatal period). This increases to 16 per cent in the first three months after having a baby

and can occur in the year following childbirth (the postnatal period). There is also ‘perinatal’ depression which covers both pregnancy and the first year after the baby’s birth. 

Bipolar disorder

Bipolar disorder affects around 2% of the population and used to be known as ‘manic depression’ because the person experiences periods of depression and periods of mania, with periods of normal mood in between. Mania is the opposite of depression and can vary in intensity – symptoms include feeling great, having lots of energy, racing thoughts and little need for sleep, talking quickly, having difficulty focusing on tasks, and feeling frustrated and irritable. 

Cyclothymic disorder

Cyclothymic disorder can be described as a milder form of bipolar disorder in which the duration of the mania or depressive episodes are shorter, less severe and not as regular.

Dysthymic disorder

The symptoms of dysthymia are similar to those of major depression but are less severe, and last longer. A person must have this milder depression for more than two years to be diagnosed with dysthymia.

Seasonal affective disorder (SAD)

SAD is a mood disorder that has a seasonal pattern, and is thought to be related to variation in light exposure in different seasons. SAD is very rare in Australia and more likely to be found in Northern Hemisphere countries with shorter days and longer periods of darkness.

Risks and complications

Suicidal thoughts and self-harm can be very real complications for those suffering from depression. 

If you are in an emergency, or at immediate risk of harm to yourself or others, please contact emergency services on 000 or visit


If you are suffering from feelings of anxiety or depression, Beyond Blue has a confidential online checklist available at 

However, if you are in any doubt that what you are feeling goes beyond feeling sad or low, contact your doctor or health professional. Don’t put it off.


Smoking, drugs and alcohol

Cigarettes and alcohol may seem to help at first, but they make things worse in the long run.

Be extra cautious with cannabis. You might see it as harmless, but research has revealed a strong link between cannabis use and mental illness, including depression, and it can hinder response to therapies and medicines.

Work and finances

It’s important to avoid too much stress including work-related stress. If your depression is caused by working too much or is affecting your ability to do your job, you may need time off to recover. However, there is evidence that taking prolonged time off work can make depression worse, and that going back to work can help you recover.


There’s no one proven way that people recover from depression, and it’s different for everyone. However, there are a range of effective treatments and health professionals who can help you on the road to recovery.  

  • Psychological treatments can help you change your thinking patterns and improve your coping skills so you’re better equipped to deal with life’s stresses and conflicts. As well as supporting your recovery, psychological therapies can also help you stay well by identifying and changing unhelpful thoughts and behaviour.
  • Medical treatments for depression are mainly based on antidepressant medication. While there is no simple explanation as to how it works, it can be very useful in the treatment of moderate to severe depression and some anxiety disorders.

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