Mood stabilisers — levels, toxicity, teratogens and trials viva

Station structure

Time: 8–10 minutes. Depth: consultant teaching registrar. Expect accurate trough timing, pregnancy hierarchy, interaction traps, and named trials — not vague “monitor bloods.”[1][3]

Core questions and model points

1. What did BALANCE show? Lithium monotherapy better than valproate monotherapy for bipolar I relapse prevention; combination also effective.[1]

2. Lithium level literacy. ~12-hour trough; ISBD/IGSLI-informed maintenance often ~0.6–0.8 mmol/L individualised; baseline renal/thyroid/calcium; recheck with illness and interacting drugs.[3][8]

3. Toxicity and EXTRIP. Recognise neuro-GI syndrome; stop lithium; level + renal panel; fluids/support; extracorporeal treatment per EXTRIP for severe poisoning.[5][8]

4. Valproate pregnancy. Dose-dependent major malformation risk (EURAP); neurodevelopmental harm (NEAD context); not routine if pregnancy possible.[6]

5. Carbamazepine genetics and induction. HLA-B*1502 and SJS/TEN in high-prevalence ancestry groups; HLA-A*3101 hypersensitivity spectrum in Europeans; CYP3A4 induction and contraceptive failure.[4][7]

6. Anti-suicide. Cipriani meta-analysis supports lithium reducing suicide-related outcomes in mood disorders.[2]

Pass criteria

• BALANCE take-home correct (Li better than VPA monotherapy).[1]
• 12-hour trough and monitoring package automatic.[3][8]
• Valproate pregnancy hierarchy stated without minimisation.[6]
• HLA-B*1502 and enzyme induction named for carbamazepine.[4][7]
• Toxicity pathway includes stop–measure–support–escalate/EXTRIP awareness.[5]