Mood stabiliser choice, lithium monitoring and pregnancy hierarchy (MEQ)

(i) Preferred strategy and evidence. For bipolar I maintenance after recurrent mania, lithium is the preferred long-term cornerstone when monitoring is feasible: BALANCE showed lithium monotherapy superior to valproate monotherapy for relapse prevention, with combination also effective; lithium also carries an anti-suicide evidence signal. Shared decision covers benefits, monitoring burden, and future pregnancy planning rather than marketing “strength.” Continue or taper olanzapine based on residual symptoms and metabolic risk once a stabiliser is established.[1][2]

(ii) Lithium practicalities. Baseline: eGFR/creatinine, U&E, TFT, calcium, pregnancy test, weight, ECG if indicated. Educate on hydration and interacting drugs. Levels are 12-hour troughs at steady state after initiation/dose change. ISBD/IGSLI-informed maintenance targets commonly around 0.6–0.8 mmol/L for many adults, individualised. Recheck early, then periodically with renal/thyroid/calcium surveillance.[3][7]

(iii) Valproate hierarchy. Do not recommend valproate as routine maintenance given pregnancy potential. EURAP shows high, dose-dependent major malformation risk; Meador NEAD shows adverse cognitive outcomes after fetal valproate. If any discussion of valproate ever occurs under exceptional frameworks, document highly effective contraception, teratogen counselling, and specialist oversight — her inconsistent contraception is a hard stop for casual use.[4][5]

(iv) Lamotrigine. Best for depression-pole prevention/maintenance rather than rapid antimanic rescue. Slow titration (classic 25 mg then 50 mg fortnightly skeleton toward ~200 mg as tolerated); slower with valproate; stop for concerning rash.[6][8]

(v) Interactions and illness. NSAIDs, ACE inhibitors/ARBs, and thiazides raise lithium. In gastroenteritis/dehydration: hold lithium, rehydrate, urgent level and renal panel when unwell, restart only when eating/drinking and levels safe — prevent chronic accumulation toxicity.[7]