Lithium Baseline Investigations — MRCPsych Paper B MCQ

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

EasyMood DisordersLithium Baseline InvestigationsMRCPsych Paper B

A 32-year-old man with bipolar disorder is about to start lithium. Which baseline assessment plan is recommended by current NICE guidance?

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

Reveal the answer and explanation

Correct answer: D — Weight or BMI, FBC, U&Es including calcium, eGFR, thyroid function, and an ECG if there is cardiovascular disease or cardiovascular risk

Explanation lettering: D = shown as B · E = shown as C · B = shown as D · C = shown as E

B is correct. Before lithium is started, NICE recommends recording weight or BMI and obtaining an FBC, U&Es including calcium, eGFR and thyroid function tests. An ECG is required when cardiovascular disease or cardiovascular risk factors are present, rather than routinely in every patient. These checks identify renal, thyroid, calcium or cardiac factors that may affect lithium safety and provide baselines for subsequent monitoring. Options A and C overemphasise liver, metabolic or pancreatic investigations used with other psychotropics. Option D includes prolactin and cortisol, which are not routine lithium baseline tests. Option E omits FBC, calcium and thyroid function while adding tests that are not routinely required. Pregnancy should additionally be excluded where applicable, but it is not applicable to this patient.

Reference: National Institute for Health and Care Excellence. Bipolar disorder: assessment and management (CG185), recommendation 1.10.14, Starting lithium. Current guideline page, 2025. https://www.nice.org.uk/guidance/cg185/chapter/recommendations