Non-selective irreversible MAOI
Isocarboxazid
Adult dose
Dose: 30mg/day initial in 1–2 divided doses; max 60mg/day
Route: PO
Frequency: OD-BD
Clinical pearls
- Treatment-resistant depression — specialist
- 14-day washout before/after switching to/from other antidepressants
Contraindications
- Cerebrovascular disease
- Phaeochromocytoma
- Concurrent SSRIs/SNRIs/TCAs/sympathomimetics/pethidine
- Liver disease
- Severe cardiovascular disease
Side effects
- Hypertensive crisis with tyramine-rich foods/sympathomimetics
- Postural hypotension
- Hepatotoxicity
- Insomnia
Interactions
- Many — see BNF
- Tyramine foods (cheese, marmite, broad beans, fermented products)
- Pethidine/tramadol — avoid
- SSRIs — wait 14 days washout (5 weeks fluoxetine)
Monitoring
- BP
- LFTs
Reference: BNF; NICE NG222; Maudsley; https://bnf.nice.org.uk/drugs/isocarboxazid/. Verify against your local formulary and the latest BNF before prescribing.
Related
Curated clinical cross-links plus same-class fallbacks.
Pathways
- Acute Behavioural Disturbance / Rapid Tranquillisation · RCEM 2022; RCPsych 2022; NICE NG10
- Self-Harm Presentation · NICE NG225 (2022)
- Capacity Assessment (Mental Capacity Act) · MCA 2005; Code of Practice
- Acute Psychosis Management · NICE CG178 2014
- Depression Management · NICE CG90 2022
- Lithium Therapy Monitoring · NICE CG185 / BNF