Southern Cross Medical Library

Southern Cross Medical Library

It is normal to experience periods of feeling down in response to life events or the stresses of everyday living. However, when a low mood persists for several weeks or more, it may be the result of depression.

The main symptom of depression (also known as major depressive disorder) is feeling down or sad most of the time and having little interest or pleasure in doing things.

Depression is a recognised mental health disorder with biological, psychological, and social components to its causes, symptoms, and treatment.

Anyone can get depression. Seeking treatment as early as possible is an important step in overcoming depression.

Causes and risk factors

Depression can be triggered by different things in different people. Sometimes there is no clear trigger for the depression.

Factors that can increase a person’s risk of developing depression include:

  • Having had depression in the past
  • A family history of depression
  • Serious loss or stress, such as the death of a partner, close family member or friend; unemployment; divorce or relationship difficulties
  • Having experienced a traumatic event in childhood, which can lead to depression later in life
  • Some medications, such as blood pressure-lowering medications and anti-migraine medications
  • Serious or chronic illnesses — such as stroke, heart attack, cancer, Parkinson's disease, diabetes, coeliac disease, multiple sclerosis, and rheumatoid arthritis
  • Some women are more likely to experience depression after childbirth. This is known medically as post-natal or postpartum depression. The likelihood of post-natal depression developing is increased if other risk factors are also present.
  • Depression in the elderly is often associated with Alzheimer’s disease or dementia.

Excessive alcohol or the use of recreational or party drugs can make depression worse.

It is estimated that one in six New Zealanders will be affected by depression at some point in their life. Depression can occur at any age and is diagnosed more commonly in women than men.


Symptoms of depression vary between individuals and each person will have a different experience of the condition.

In general, the most common signs of depression (including post-natal depression) are:

  • Feeling down, depressed, or hopeless
  • Having little interest or pleasure in doing things
  • Early morning awakening.

Other symptoms of depression include:

  • Irritability/mood swings
  • Tearfulness
  • Low self-esteem/low motivation
  • Difficulty thinking clearly, making decisions, and concentrating
  • Memory difficulties
  • Reduced sex drive (libido)
  • Feelings of emptiness or loneliness
  • Feelings of worthlessness
  • Anxiety
  • Thoughts of hopelessness or suicide.

Physical symptoms of depression include:

  • Back pain
  • Headaches
  • Loss of energy
  • Significant weight loss or weight gain
  • Fatigue
  • Sleep problems
  • Changes in appetite.

Children and young people with depression can exhibit symptoms such as:

  • Anger and aggression
  • Risk-taking behaviours
  • Significant mood swings
  • Social isolation
  • Being quiet and shy
  • Denying that something is wrong.

People with depression also have a greater chance of developing panic attacks and phobias.


If depression is suspected, it is important to see a doctor so that an accurate diagnosis can be made and appropriate treatment given.

There is no medical test that can diagnose depression. However, doctors use documented criteria to help diagnose the condition based on a person’s symptoms and duration of those symptoms.

Blood tests to check for underlying conditions or deficiencies (eg: hypothyroidism) may be recommended.


The earlier treatment for depression is started, the better the chances of successful treatment. Carefully following the prescribed treatment plan is also vital in treating depression and preventing its recurrence.

Treatment of depression will be tailored to each individual and will involve several important components. The needs of the individual and the stage and severity of the depression will be considered when planning treatment. The three main treatment approaches for depression are self-help techniques, psychological therapies and medications.

Self-help techniques:

Self-help techniques that can help combat depression include:

  • Regular exercise
  • Maintaining a healthy, balanced diet
  • Reducing alcohol, caffeine, and tobacco intake
  • Having a regular bedtime and waking up time (ie: good sleep habits)
  • Recognising when time out is needed, and taking it
  • Making time to undertake an enjoyable activity each day
  • Asking for and/or accepting support from friends and families to achieve self-help goals.

Psychological therapies:

This is essentially ‘talking therapy’ and may be recommended alone in cases of mild depression. In cases of moderate and severe depression, it may be recommended in addition to antidepressant medications.

There are a number of different psychological therapy techniques, including:

  • Cognitive behavioural therapy (CBT) involves helping a person to change negative ways of thinking and behaving that are associated with their depression
  • Interpersonal psychotherapy (ITP) focusses on a person's dysfunctional personal relationships that cause depression or make the depression worse
  • Problem-solving therapy (PST) is a form of psychotherapy that aims to help you develop coping skills to manage upsetting life experiences.


Antidepressants are the mainstay medications for depression.

Other medications such as anti-psychotics and sedatives may be used in conjunction with antidepressant medications in some cases.

As it is difficult to predict how a person will respond to and tolerate a particular antidepressant medication, a process of trial and error may be required until an effective medication for that person is found.

Antidepressant medications are not addictive. However, they can cause unpleasant side effects if stopped suddenly. Antidepressant medications should only be discontinued while under the supervision of a doctor.

Electroconvulsive therapy (ECT):

Uncommonly, and only in cases of severe depression where other treatments have been unsuccessful, electroconvulsive therapy (ECT) may be recommended. ECT is a highly effective treatment for depression. It involves passing an electric current across the head after a muscle relaxant and general anaesthetic has been administered.

The exact reason ECT is effective is not fully understood but it is thought to affect the chemical balance in the brain, leading to stabilisation of mood and reduction of depression.

Further information and support

Your GP or practice nurse can provide information and support about depression.

The following services can also provide support to people suffering from depression, as well as to their friends and family.

Depression Helpline

Freephone: 0800 111 757


Freephone: 0800 543 354
Text: ‘Help’ to 4357


Freephone: 0800 376 633
Free text: 234


Freephone: 0800 726 666

Mental Health Foundation of New Zealand

(for information and resources about depression)
Phone: (09) 623 4812
E-mail: [email protected]


Halverson, J.L. (2020). Depression (Web page). Medscape Drugs and Diseases. New York, NY: WebMD LLC. [Accessed: 09/10/20]
Mayo Clinic (2018). Depression (major depressive disorder) (Web Page). Rochester, MN: Mayo Foundation for Medical Education and Research. [Accessed: 09/10/20]
Mental Health Foundation (2014). Depression (Web Page). Auckland: Mental Health Foundation of New Zealand. [Accessed: 09/10/20]
O’Toole, M.T. (Ed.) (2016). Depression. Mosby’s Dictionary of Medical, Nursing & Allied Professions (10th ed.). St Louis, MI: Elsevier Mosby.
RANZCP (2017). Depression — Your Guide (PDF booklet). Melbourne, VIC: Royal Australian and New Zealand College of Psychiatrists.

Updated: October 2020

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The purpose of the Southern Cross Medical Library is to provide information of a general nature to help you better understand certain medical conditions. Always seek specific medical advice for treatment appropriate to you. This information is not intended to relate specifically to insurance or healthcare services provided by Southern Cross.