Suicidal ideation with a plan, intent, or recent self-harm: urgent mental health or ED assessment and a safety plan now. Ask directly about suicide; asking does not increase risk.
First-line SSRI (typical)
- Sertraline is a common first choice
- Check QT risk and interactions (citalopram, escitalopram)
- Start low in older people and review for hyponatraemia
- Allow an adequate dose for 4 weeks (less in younger people) before judging response
Early review
- Review within 1 week if under 30 or at higher suicide risk; otherwise within 2 weeks
- Warn of early activation, nausea, and a possible transient rise in anxiety
- Combine with a psychological therapy where possible
Less severe (PHQ-9 under 16)
- Guided self-help, exercise, CBT
- Do not routinely offer a drug first
- Review and monitor
More severe (16 or more)
- Offer an antidepressant (SSRI first line)
- Or psychological therapy
- Review within 1 to 2 weeks
Risk / crisis
- Active suicidal ideas or plan
- Psychosis or severe self-neglect
- Urgent mental health referral
Stepwise care
1
1. Assess
Severity and functional impact (PHQ-9 or clinical assessment). Screen for bipolar history (antidepressant can precipitate mania), psychosis, and alcohol or substance use.
Severity and functional impact (PHQ-9 or clinical assessment). Screen for bipolar history (antidepressant can precipitate mania), psychosis, and alcohol or substance use.
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2
2. Start
SSRI first-line with clear advice on the lag to benefit (often 2 to 4 weeks), side effects, and bleeding risk with NSAIDs (add a PPI if needed).
SSRI first-line with clear advice on the lag to benefit (often 2 to 4 weeks), side effects, and bleeding risk with NSAIDs (add a PPI if needed).
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3
3. Switch or augment
If little response at an adequate dose and duration, check adherence then switch SSRI or class. Specialist advice for augmentation or treatment resistance.
If little response at an adequate dose and duration, check adherence then switch SSRI or class. Specialist advice for augmentation or treatment resistance.
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4
4. Continue and stop
Continue for at least 6 months after remission. Taper slowly over weeks to months to reduce discontinuation symptoms (especially paroxetine, venlafaxine).
Continue for at least 6 months after remission. Taper slowly over weeks to months to reduce discontinuation symptoms (especially paroxetine, venlafaxine).
Safety points
- Serotonin syndrome risk with tramadol, triptans, MAOIs, linezolid
- Hyponatraemia, especially in older people
- GI bleeding risk, more so with NSAIDs or anticoagulants
- Do not stop abruptly
Pitfalls
- Starting an antidepressant in undiagnosed bipolar disorder
- No early review in a young or high-risk patient
- Declaring failure before an adequate trial
- Abrupt cessation causing discontinuation symptoms
MedPrep - www.medprep.uk - Educational revision aid only. Not clinical guidance. Doses are adult examples; check the BNF, current guidelines and local policy, and seek senior advice. Nov 2026