Psychiatry
Depression and Depressive Disorders
Depression for MBBS and NEET-PG: core and biological symptoms, suicide risk, SSRIs and tricyclics, serotonin syndrome, ECT and CBT, mapped to NMC codes PS6.
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Depression and Depressive Disorders
Depression for MBBS and NEET-PG: core and biological symptoms, suicide risk, SSRIs and tricyclics, serotonin syndrome, ECT and CBT, mapped to NMC codes PS6.
This chapter covers unipolar depression from recognition to treatment. It sets out the core and biological symptoms, the assessment of suicide risk, the antidepressant classes and their cautions, serotonin syndrome, the role of electroconvulsive therapy and cognitive behavioural therapy, and special situations such as postnatal and elderly depression.
High-yield: Depression and Depressive Disorders
- The core features of a depressive episode are persistent low mood, loss of interest or pleasure and reduced energy lasting at least two weeks.
- Biological symptoms include early morning waking, diurnal mood variation worse in the morning, loss of appetite, weight loss and reduced libido.
- The monoamine hypothesis links depression to reduced serotonin, noradrenaline and dopamine activity.
- Every depressed patient must be assessed for suicidal ideas, plans and intent, as suicide is the most serious complication.
- Selective serotonin reuptake inhibitors such as fluoxetine and sertraline are first-line because of their favourable safety profile.
- Antidepressants take about two to four weeks to show benefit, and the risk of acting on suicidal thoughts can rise early as energy returns before mood lifts.
- SSRIs are continued for at least six months after recovery to reduce the risk of relapse.
- Tricyclic antidepressants are effective but dangerous in overdose because of cardiac arrhythmia.
- Serotonin syndrome causes agitation, tremor, hyperreflexia, clonus, fever and autonomic instability, usually from combining serotonergic drugs.
- Combining an SSRI with a monoamine oxidase inhibitor can precipitate serotonin syndrome and is contraindicated.
- Electroconvulsive therapy is highly effective for severe depression with strong suicidal risk, psychotic features or refusal to eat and drink.
- Cognitive behavioural therapy is an evidence-based psychological treatment, alone in mild cases and with medication in moderate to severe illness.
- Postnatal depression and depression in the elderly, where it may mimic dementia as pseudodementia, are important special situations.
- Depression is recurrent in many patients, so relapse prevention and family education are part of long-term care.
Antidepressants and cautions
- **SSRIs:** Fluoxetine, sertraline. First-line; safer in overdose; onset in two to four weeks.
- **Tricyclics:** Effective but dangerous in overdose due to cardiac arrhythmia.
- **Serotonin syndrome:** Agitation, tremor, clonus, fever. Avoid combining SSRI with MAO inhibitor.
- **ECT:** For severe depression with high suicidal risk, psychosis or food and fluid refusal.
NMC competencies in this chapter
- **PS6.1:** Clinical features of depression
- **PS6.2:** Indications and interpretation of investigations in depression
- **PS6.3:** Treatment of depression including behavioural methods
- **PS6.4:** Family education in depression
- **PS6.5:** Pharmacological basis and side effects of antidepressants
- **PS6.6:** Conditions for specialist referral in depression
- **PS6.7:** Assessment and management of suicidal risk
Frequently Asked Questions
What are the biological symptoms of depression?
They include early morning waking, diurnal mood variation that is worse in the morning, loss of appetite with weight loss, and reduced libido, and they help identify a more severe, treatable depression.
Why does suicide risk sometimes rise early in treatment?
Antidepressants can restore energy and drive before mood fully lifts, so a patient may become more able to act on existing suicidal thoughts. Close monitoring in the first weeks is essential.
When is electroconvulsive therapy used?
Electroconvulsive therapy is used in severe depression with a high suicidal risk, psychotic features, or refusal to eat and drink, and where a rapid response is needed or medication has failed.
What is serotonin syndrome?
It is a potentially dangerous reaction from excess serotonin, with agitation, tremor, hyperreflexia, clonus, fever and autonomic instability, often from combining serotonergic drugs such as an SSRI with an MAO inhibitor.
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