Normal range 4.2-6.4 mmol/L (75-115 mg/dL)

Conversion factor

• mg/dL x 0.555 = mmol/L
• mmol/L x 18 = mg/dL

Patients who are unconscious or confused should have a finger prick test performed to estimate their blood sugar.

Testing for hypoglycaemia is obviously important in diabetic patients who may have overdosed on their medication. It also may occur in patients with large ingestions of alcohol, glycols or salicylates, and in patients who have hepatotoxicity from any cause.

Formal blood glucose should also be estimated.

A raised glucose is suggestive of poisoning with sympathomimetic drugs (e.g. theophylline, beta agonists, and amphetamines), calcium channel blockers or salicylates.