Hypokalaemia Bulimia Emergency — MRCPsych Paper B MCQ

Correct answer: C — Arrange urgent hospital admission for intravenous potassium correction with cardiac monitoring

The correct answer is C. Potassium of 2.3 mmol/L is severe hypokalaemia and a high-risk medical finding in an eating disorder. Palpitations and ventricular ectopic beats indicate immediate arrhythmic risk, requiring urgent hospital admission, potassium correction—initially intravenous in this context—and cardiac and biochemical monitoring. A normal BMI does not reduce the risk arising from rapid electrolyte loss through purging. Fluoxetine and family-based treatment may form part of subsequent bulimia treatment but must not delay medical stabilisation. Increasing calories alone will not promptly correct the arrhythmogenic electrolyte disturbance and should occur within an appropriately monitored treatment plan. Discharge is unsafe. Once medically stable, specialist eating-disorder care should address vomiting and other maintaining behaviours to prevent recurrence.

Reference: Royal College of Psychiatrists. Medical Emergencies in Eating Disorders: Guidance on Recognition and Management (MEED), CR233, Table 1 and Table 2: hypokalaemia and management of clinical findings. May 2022. https://www.rcpsych.ac.uk/docs/default-source/improving-care/better-mh-policy/college-reports/college-report-cr233-medical-emergencies-in-eating-disorders-%28meed%29-guidance.pdf?sfvrsn=2d327483_59