Psych MEQs / SAQs · Psychopharmacology — lithium
Initiating and monitoring lithium in bipolar I with suicide risk (MEQ)
FRANZCP-style MEQ on lithium initiation, TDM, interactions, suicide evidence, and toxicity/EXTRIP.
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(i) Offer lithium. Long-term RCTs/meta-analyses support lithium for bipolar relapse prevention (Geddes). BALANCE: lithium monotherapy and lithium–valproate combination both beat valproate monotherapy for any mood episode in bipolar I — so valproate alone is not an evidence-equivalent default. Cipriani 2013: lithium reduces suicides and all-cause deaths versus placebo in mood-disorder RCTs — highly relevant after a serious attempt. Frame as gold-standard maintenance with monitoring, not "too dangerous to discuss."[1][2][3]
(ii) Pre-start and consent. Baseline U&E/creatinine/eGFR, TFT, calcium, weight, pregnancy test when relevant, ECG if indicated; full drug history including OTC NSAIDs. Consent: narrow therapeutic index, need for 12-hour troughs and organ bloods, common effects (tremor, polyuria, weight), toxicity red flags, sick-day rules for severe vomiting/diarrhoea/dehydration, contraception/pregnancy plans. Confirm service can deliver monitoring.[4][6][7]
(iii) Initiation and TDM. Start low (e.g. lithium carbonate 250–500 mg/day product-dependent), titrate using clinical response and 12-hour trough levels at steady state. Maintenance scaffold often about 0.6–0.8 mmol/L; individualise. Early denser levels then regular level + eGFR/TFT/calcium calendar per local protocol (principles: more frequent early and after any clearance change).[6][7]
(iv) Interactions. Advise stopping casual ibuprofen; prefer paracetamol for simple analgesia if appropriate; warn that NSAIDs, ACEI/ARB, thiazides and dehydration raise lithium levels and can cause chronic toxicity. Provide written list and GP communication.[5][6]
(v) Toxicity. Stop lithium and precipitants; ABC; IV isotonic saline if volume depleted; serial levels, renal panel, ECG. Charcoal does not bind lithium. EXTRIP: ECTR recommended in severe poisoning and when impaired kidney function coexists with high concentration, or decreased consciousness/seizures/life-threatening dysrhythmias irrespective of level; HD preferred; watch rebound.[5][6]
Common errors
- Treating valproate monotherapy as equivalent to lithium for bipolar I prophylaxis despite BALANCE.[2]
- Omitting anti-suicide RCT evidence when suicide risk is prominent.[3]
- Using random non-trough levels for dose decisions.[7]
- Ignoring OTC NSAIDs in interaction counselling.[6]
- Recommending activated charcoal as lithium-binding decontamination.[5]
References
- [1]Geddes JR, Burgess S, Hawton K, et al. Long-term lithium therapy for bipolar disorder: systematic review and meta-analysis of randomized controlled trials Am J Psychiatry, 2004.PMID 14754766
- [2]BALANCE investigators and collaborators, Geddes JR, Goodwin GM, et al. Lithium plus valproate combination therapy versus monotherapy for relapse prevention in bipolar I disorder (BALANCE): a randomised open-label trial Lancet, 2010.PMID 20092882
- [3]Cipriani A, Hawton K, Stockton S, et al. Lithium in the prevention of suicide in mood disorders: updated systematic review and meta-analysis BMJ, 2013.PMID 23814104
- [4]McKnight RF, Adida M, Budge K, et al. Lithium toxicity profile: a systematic review and meta-analysis Lancet, 2012.PMID 22265699
- [5]Decker BS, Goldfarb DS, Dargan PI, et al. Extracorporeal Treatment for Lithium Poisoning: Systematic Review and Recommendations from the EXTRIP Workgroup Clin J Am Soc Nephrol, 2015.PMID 25583292
- [6]Gitlin M Lithium side effects and toxicity: prevalence and management strategies Int J Bipolar Disord, 2016.PMID 27900734
- [7]Hiemke C, Bergemann N, Clement HW, et al. Consensus Guidelines for Therapeutic Drug Monitoring in Neuropsychopharmacology: Update 2017 Pharmacopsychiatry, 2018.PMID 29390205