Depression or major depressive disorder (MDD) is a broad term used to describe a large number of disorders characterised by a depressed mood and a loss of interest in usual activities. 1

It can occur as a single episode or on a recurring basis.2 Depressed mood and loss of interest or pleasure in almost all activities must be present for a correct diagnosis plus four or more of the following symptoms:3

  • Significant weight loss or gain or an increase or decrease in appetite
  • Sleeping disturbances such as insomnia or sleeping far more than usual
  • Tiredness or loss of energy
  • Difficulty thinking and concentrating or indecisiveness
  • Agitation
  • Feelings of worthlessness, hopelessness or excessive/inappropriate guilt
  • Recurring thoughts of death – fear of dying or suicide
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Depression is one of the most commonly diagnosed disorders. 4 It can occur at any age, even childhood and adolescence, but the twenties and thirties are generally the most common age groups. 3 Risk factors include age and gender with women being higher risk than men.

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Many factors contribute to depressive symptoms and disorders. These include genetics (family history), stress, environmental and social factors, but the exact cause is unclear. 5 What we do know is that there are three major neurotransmitters in the brain called serotonin, noradrenaline and dopamine, which are linked to depression.

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Depressed mood is one of the two required symptoms for MDD diagnosis. It is the most widely recognised symptom and the one most often targeted by treatment. 8

Serotonin and noradrenaline influence mood. Antidepressants that act on either serotonin, noradrenaline or both have been associated with the normalisation of these circuits.

This can potentially explain how antidepressants can improve feelings of sadness and depressed mood. 8

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The World Health Organisation (WHO) ranks depression as the single most burdensome disease in the world. It is a chronic disorder and can severely affect every aspect of people’s lives and ability to function. 4 Even mild depression can affect quality of life. Statistics show that the rate of suicide in depressed patients is increasing. 9

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Most patients return to normal functioning once an episode is over but, untreated, approximately 50 – 85% of sufferers will eventually have another episode. 3, 9 The main treatment goal is remission (no depressive symptoms), so that sufferers can regain their ability to function properly and improve their quality of life. Treatment can also reduce depression symptoms and limit the recurrence of future depressive episodes. 9

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Treatment may include:

  • Anti-depressant medication or
  • Depression-focused psychotherapy, or
  • A combination of the two.
  • There are other therapies such as electroconvulsive therapy (ECT), transcranial magnetic stimulation (TMS), and vagal nerve stimulation, but these are used in more resistant cases of severe depression. 3, 9
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Antidepressants differ in the way they work, how they interact with other medications, their side effects and how easily the dosage can be adjusted. If you don’t respond well to one type of antidepressant, it doesn’t mean that you won’t respond well to another one. 10

When starting an antidepressant, your doctor will generally prescribe a lower dose for a minimum of four weeks before increasing the dose or changing your medication. 11 It may take six to eight weeks for you to respond to the medication initially, although some improvement is usually noted from two weeks onwards. 3, 12

It is generally recommended that antidepressant therapy be continued for:

  • A year following the onset of symptoms for the first episode
  • At least two years if you have any additional risk factors

Additional risk factors include severe (difficult-to-treat) depression without improvement, older people and people with other associated diseases. 12

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Psychotherapy is a “talk therapy” to help sufferers to develop healthy coping mechanisms to deal with daily stress. When undertaken in conjunction with prescribed medication, it can address and even resolve MDD. 9

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The vast majority of people with depression respond well to treatment. The first step in treating depression is to discuss your symptoms with your general practitioner or a healthcare professional at your local day clinic or hospital.

More Information here Download PDF Medical References

Medical References

1. Soleimani L, Lapidus K, Iosifescu DV. Diagnosis and Treatment of Major Depressive Disorder. Neurol Clin 2011;29:177–193.

2. Akiskal AS. Mood Disorders. Clinical Features. In: Kaplan and Sadock’s Comprehensive Book of Psychiatry. Sadock BJ, Sadock VA, Pedro R editors. 9th ed. Philadelphia. Wolters Kluwer Health/Lippincott Williams & Wilkins 2009. Chapter 13.7.

3. Grobler G. Major Depressive Disorder. The South African Society of Psychiatrists (SASOP) Treatment Guidelines for Psychiatric Disorders. SAJP 2013;19(3):130-196.

4. Richards D. Prevalence and clinical course of depression: A review. Clinical Psychology Review 2011;31:1117–1125.

5. Coryell W. Depressive Disorders. The Merck Manual.[online] 2013, December. [cited 2014, August 18] Available at

6. Stahl SM. Circuits in Psychopharmacology. In: Stahl’s Essential Psychopharmacology. Neuroscientific Basis and Practical Application. Cambridge University Press, Cambridge. Third Edition 2008.Chapter 7:195-222.


8. Stahl SM, Zhang L, Damatarca C, Grady M. Brain Circuits Determine Destiny
in Depression: A Novel Approach to the Psychopharmacology of Wakefulness,
Fatigue, and Executive Dysfunction in Major Depressive Disorder J Clin Psychiatry 2003;64[suppl 14]:6–17.

9. Gelenberg AJ, Freeman MP, Markowitz JC, Rosenbaum JF, Thase ME, Trivedi MH,et al. Practice Guideline For The Treatment of Patients With
Major Depressive Disorder. Third Edition. American Psychiatric Association. 2010:11-152.

10. Rush AJ, Nierenberg AA .Mood Disorders: Treatment of Depression. In:
Kaplan and Sadock’s Comprehensive Book of Psychiatry. Sadock BJ, Sadock VA, Pedro R editors. 9th ed. Philadelphia. Wolters Kluwer Health/Lippincott Williams & Wilkins 2009. Chapter 13.8.

11. Choe CJ, Emslie GJ, Mayes TL. Depression. Child Adolesc Psychiatric Clin N Am 2012;21:807–829

12. Mahli GS, Hitching R, Berk M, Boyce P, Porter R, Fritz K. Pharmacological management of unipolar Depression. Acta Psychiatr Scand 2013: 127 (Suppl. 443): 6–23.

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