≥2 weeks of low mood / anhedonia plus ≥4 SIGECAPS symptoms causing functional impairment.
History taking
- • Onset, duration, progression, severity
- • Aggravating / relieving factors
- • Past history, drugs, allergies, comorbidities
- • Family & social history relevant to presentation
Examination
- • General: vitals, pallor, icterus, oedema, lymphadenopathy
- • Focused system examination
- • Look for red-flag findings
Red flags
- • Active suicidal ideation with plan → urgent psychiatry
Differential diagnosis
- • See differentials section per chief complaint
Recommended investigations
- • PHQ-9 score
- • TSH, B12, basic labs to exclude organic
Diagnosis
- • Clinical diagnosis supported by targeted investigations
Initial treatment / management
- • Treat underlying cause
- • Symptomatic relief
- • Patient education
Drug therapy
- • Sertraline 50 mg OD (start), titrate q2 weeks
- • Escitalopram 10 mg OD
- • Mirtazapine 15–45 mg ON (sleep / appetite)
Follow-up advice
- • Review at 1–2 weeks (esp. under 25), then 4 weekly
- • Continue ≥6 months after remission
Patient counselling
- • Discuss suicide risk, support network
- • Avoid alcohol
- • Sleep hygiene, exercise
Referral criteria
- • Refer if diagnostic uncertainty, complications, or failure of first-line therapy
References
- • Harrison's Principles of Internal Medicine, 21e
- • NICE / WHO guidelines (current edition)
Educational outpatient guide — verify against local guidelines before clinical use.
