skip to main content

Lithium toxicity — SCE Acute Medicine MCQ

Instant feedback + full explanation. One question, done properly.

HardToxicology and OverdoseLithium toxicitySCE Acute Medicine

A 70-year-old woman taking lithium for bipolar disorder presents with vomiting, tremor and ataxia after starting bendroflumethiazide. Creatinine is 198 micromol/L and lithium concentration is 2.9 mmol/L. ECG shows T-wave flattening and she is increasingly confused. What is the most appropriate next step in management?

Educational content. Not a substitute for clinical judgement or local policy.

Reveal the answer and explanation

Correct answer: E — Stop lithium, give intravenous fluids and discuss haemodialysis urgently

Neurological toxicity, renal impairment and a high lithium concentration require stopping lithium, volume repletion and urgent toxicology or renal discussion about haemodialysis. Thiazides commonly precipitate lithium toxicity by reducing renal clearance. Propranolol would mask signs without treating toxicity. The pearl is that clinical features are often more important than the number alone.

Reference: TOXBASE; BNF lithium monitoring