Valproate for mania: loading, levels, pregnancy hierarchy and ammonia (MEQ)

(i) Antimanic justification. Valproate/divalproex is a reasonable first-line oral antimanic when lithium is unsuitable: Bowden established divalproex superiority to placebo in mania. Note honestly that for long-term bipolar I maintenance, BALANCE found lithium monotherapy superior to valproate monotherapy — separate acute from maintenance counselling.^[1][2]

(ii) Loading, titration, levels. If oral intake allows, accelerated oral loading (teaching frameworks ~20–30 mg/kg/day) can rapidly achieve therapeutic serum concentrations (Hirschfeld lineage); otherwise start ~500–1000 mg/day and titrate. Measure trough levels at steady state after load/dose change. Class teaching often cites ~50–100 mg/L for bipolar use, with concentration–response data supporting adequate levels in acute mania; individualise to response and tolerability per product information.^[3][4]

(iii) Monitoring. Baseline: LFT, FBC/platelets, weight, drug interactions, consent. Ongoing: clinical review (tremor, sedation, GI, cognition), weight, periodic LFT/FBC, levels when non-response/toxicity/adherence/interaction issues. Ammonia if new confusion or reduced alertness even if LFT look modest — hold valproate and treat hyperammonaemic encephalopathy pathway.^[7]

(iv) Pregnancy hierarchy. Do not use as routine bipolar care if pregnancy possible. EURAP: high dose-dependent major malformation risk; NEAD: adverse cognitive outcomes after fetal exposure; Christensen: increased ASD risk association. Prefer alternatives; exceptional use needs specialist framework and highly effective contraception.^[5][6][8]

(v) Lamotrigine. Valproate inhibits lamotrigine metabolism → slower LTG titration and typically lower doses to reduce serious rash risk — confirm titration schedule against local product information.^[7]