REVIEW ARTICLE

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DEPRESSION IN PRIMARY CARE
PART 2: MANAGEMENT

Pharmacological therapies

Most depressive disorders require treatment with antidepressants.⁷ There is a tendency for general practitioners in Malaysia to use benzodiazepines like alprazolam to treat depression.  There is no evidence to show that benzodiazepines have antidepressant properties. They are useful in alleviating symptoms of anxiety and providing sedation in depressed patients⁴.

Tricyclic and tetracyclic antidepressants (TCAs) and the selective serotonin reuptake inhibitors (SSRIs) are the commonly used antidepressants in clinical practice. The main advantages of the SSRI group over the TCA group are that they produce fewer side effects and are safe in overdose.  On the other hand, patented SSRIs are much more expensive than TCAs. There are also other newer antidepressants like the SNRIs (serotonin and noradrenaline reuptake inhibitors), mirtazapine and escitalopram.

Table 1: Comparison of Classes of Commonly Used Antidepressants in Malaysia

Anti-depressants	Action	Common side effects	Cost
Tricyclic antidepressants (amitryptiline, imipramine, dothiepin)	Blockade of serotonin and noradrenaline uptake	• Sedation • Anticholinergic effects (dry mouth, blurred vision, constipation, urinary retention) • Postural hypotension • Weight gain • Sexual dysfunction • Toxic in overdose	Generic – RM 0.50 to RM 1.50 per tablet (lowest dose)
SSRIs (sertaline, fluoxetine, citalopram, fluoxamine, paroxetine)	Blockade of serotonin uptake	• Transient increase in anxiety or nausea in increasing dose • Sexual dysfunction	• RM 3.00 to RM 6.00 per tablet (lowest dose) • Generic is cheaper costing RM 1.00 to RM 2.00 (lowest dose)
SNRIs (venlafaxine, duloxetine)	Blockade of serotonin and noradrenaline uptake	• Initial increase in anxiety and nausea • Sexual dysfunction • Hypertension (venlafaxine)	RM 4.00 to RM 6.00 per capsule (lowest dose)

Choosing Anti-depressants

Factors to consider when choosing a first-line antidepressant medication:⁷

• Anticipated side effects and tolerability
• Safety in overdose
• History of prior response in patient
• Patient preference
• Cost of medication

The SNRIs and escitalopram can be utilized as second line antidepressants when the first line antidepressants are ineffective or fail to bring about the desired outcome. When sedation is required it is preferable to use a sedating antidepressant like mirtazapine or the TCAs. Alternatively a non-sedating antidepressant can be prescribed with a benzodiazepine or a non-benzodiazepine sedative hypnotic like zolpidem. The sedative hypnotic should be taken only for short periods of time because of the risk of dependence. Most of the SSRIs are non-sedative but some patients may complain of drowsiness with fluvoxamine and paroxetine.

Side effect tolerability depends on the individual patient. Some individuals tolerate side effects better than others. It must be remembered that no anti-depressant is devoid of side effects.

In patients with co-morbid medical illness, an antidepressant with fewer drug-to-drug interactions should be prescribed.⁴ Citalopram, sertraline, venlafaxine and mirtazapine fall into this category.

If the patient has been successfully treated with antidepressants in the past, the same antidepressant often proves to be effective in a recurrent episode of depression.⁸

The patient with thoughts of self-harm should be assessed for suicide risk. Patients with low suicide risk can be treated in primary care with safe antidepressants namely SSRIs.⁸