Hypoglycaemia Risk — ORE Part 1 MCQ

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ModerateHuman Disease & Dental ManagementHypoglycaemia RiskORE Part 1

A 65-year-old patient taking metformin and gliclazide for type 2 diabetes presents for dental extractions. Their blood glucose is 4.2 mmol/L before the appointment. What is the main risk during the dental procedure?

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Correct answer: E — Hypoglycaemia, due to gliclazide-induced insulin secretion

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

The correct answer is A. Gliclazide, a sulphonylurea, directly stimulates pancreatic insulin secretion independent of blood glucose level. The patient's pre-operative glucose (4.2 mmol/L) is already at the lower margin of acceptable range; combined with fasting during the procedure and stress-induced glucose utilisation, gliclazide-mediated insulin secretion presents substantial acute hypoglycaemia risk. Metformin does not cause hypoglycaemia. Hyperglycaemia (B) may occur later due to stress, but acute perioperative risk is hypoglycaemia. DKA (C) is rare in type 2 diabetes outside severe metabolic decompensation. Metformin-associated lactic acidosis (D) requires severe renal impairment or sepsis, not routine dental extraction. Option E is false given the clinical presentation.

Reference: Gliclazide Safety and Efficacy meta-analysis (PLoS One 2014) and CGMS studies on sulphonylurea-induced hypoglycaemia; NICE Guideline NG28 (Type 2 Diabetes in Adults: Management, updated 2022); https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3922704/ and https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4653430/