Dexamethasone Antiemetic Dosing — SCE Palliative Medicine MCQ

Correct answer: C — Separate once-daily SC dexamethasone

In UK palliative care, dexamethasone as an adjuvant antiemetic for refractory nausea is given at much lower doses (generally 4–16 mg orally, or approximately 6.6–13.2 mg parenterally) as a separate bolus rather than included in a syringe‑driver, due to formulation and compatibility issues. Option C reflects this practice and distinguishes it clearly from the much higher 16 mg (“cerebral oedema”) dose or ultra‑high pulse therapies, or implausible routes like nebulisation. Lower doses (e.g., 0.5 mg) are ineffective. Nebulised use lacks evidence. Hence, A is the only defensible choice. Apply this conclusion only to the clinical circumstances stated, with appropriate specialist review, contraindication checks, shared decision-making and follow-up. Reassess if the physiology, treatment response or competing risk changes. The competing options would require a different haemodynamic profile, diagnosis, procedural indication or risk balance from the one described here.

Reference: NHS England Palliative Care guidelines: "Refractory nausea and vomiting: 8‑16 mg orally OR 6.6‑13.2 mg each morning" (2020); Palliative Care Clinical Practice Summary: "Refractory nausea and vomiting: 4‑8 mg daily" (2022): https://bnf.nice.org.uk/