Hypoglycaemia — Bleepd

Hypoglycaemia = blood glucose <4.0 mmol/L. Treat even without symptoms.

Act now

1
Able to swallow: 15–20 g quick-acting carbohydrate (e.g. 4–5 glucose tablets, 60 mL Glucojuice or 150–200 mL pure fruit juice). Recheck after 10–15 minutes; repeat up to 3 times.
2
Can swallow but uncooperative: 1.5–2 tubes of 40% glucose gel into the buccal space; or IM glucagon.
3
Unconscious, fitting or nil by mouth: IV glucose (see prescribing notes), or IM glucagon if no IV access.

Assess

Conscious and able to swallow? Confused/uncooperative? Unconscious, fitting, or nil by mouth?
Stop any IV insulin infusion.

Investigations

Recheck glucose after 10–15 minutes and regularly afterwards; U&E (renal impairment prolongs sulfonylurea and insulin action).

Manage

Once above 4.0 mmol/L: give 20 g long-acting carbohydrate (40 g if glucagon was used), e.g. two biscuits or a slice of bread.
If nil by mouth, run 10% glucose at 100 mL/h until reviewed.
Do not omit subsequent insulin in type 1 diabetes — review doses instead.
Find the cause and refer to the diabetes team.

Escalate when

Recurrent, prolonged or sulfonylurea-induced hypoglycaemia, or reduced consciousness after correction: senior review; consider adrenal insufficiency.

Doses and prescribing

IV glucose over 10–15 minutes: 100 mL of 20% or 200 mL of 10% per JBDS-IP. Some local protocols use 75 mL 20% / 150 mL 10% — follow yours. Avoid 50% (extravasation risk).

Glucagon

1 mg IM once only; may be ineffective in malnutrition, severe liver disease, repeated or sulfonylurea-induced hypoglycaemia — use IV glucose instead.

Check the BNF and your local formulary before prescribing.

Written to current guidance · sources checked 14 Nov 2026. We watch NICE for updates weekly.

Sources (2)

Reviewed by Aboodee Alhasso, MPharm MRCPharm IP on 14 Nov 2026

For healthcare professionals, as an aid to clinical judgement — not a substitute for it. Follow your local policy and ask a senior when in doubt.