Hypoglycemia
at the bedside
- capillary glucose now; treat first if symptomatic, seizing or unconscious
- unexpected result → repeat, or lab glucose, after starting treatment
- consciousness, swallow, IV access
- levels
- level 1 → glucose < 3.9 and ≥ 3.0 mmol/L
- level 2 → glucose < 3.0 mmol/L
- level 3 → needs help from another person, whatever the number
reduced consciousness, seizure or unsafe swallowing
- call for help, protect the airway
- glucose 10% 150–200 mL IV or glucose 20% 75–100 mL IV over 10–15 min; alternative glucose 50% 50 mL IV
- no IV access → glucagon 1 mg IM, keep working for access
- recheck glucose at 10–15 min; still low → repeat
- recurrent or not holding → glucose 10% IV infusion, titrated to glucose
- on a sulfonylurea → it will recur; once awake → after recovery
escalate now if
- persistent or recurrent hypoglycemia despite repeated treatment, or needing a glucose infusion
- seizure, reduced consciousness or focal neurology after glucose has corrected
- suspected sulfonylurea or long-acting insulin overdose
- hypoglycemia without diabetes
- suspected adrenal crisis
focused check
- symptoms
- autonomic → sweating, palpitations, tremor, nausea
- neuroglycopenic → confusion, behavioral change, focal deficits, seizures
- cause
- diabetes treatment; time and dose of the last insulin; sulfonylurea or meglitinide, recent dose changes
- missed meals, NPO, vomiting, alcohol
- acute illness, renal or hepatic deterioration
- weight loss, hypotension, recent steroid withdrawal → adrenal insufficiency
send now
- RFT, LFT; infection screen if suspected
- adrenal insufficiency suspected (hypotension, hyponatremia, hyperkalemia, weight loss, hyperpigmentation, recent steroid withdrawal) → 8–9 AM cortisol ± ACTH; a single cortisol does not rule it out; in suspected crisis take the sample only if it does not delay steroids
- no diabetes, or unexplained → during the low, before treating if no delay: lab glucose, insulin, C-peptide, β-hydroxybutyrate, sulfonylurea screen
treat
conscious and able to swallow
- 15–20 g fast-acting carbohydrate (table)
- recheck glucose at 10–15 min; still < 4 mmol/L → repeat, up to 3 cycles
- above 4 mmol/L → longer-acting carbohydrate if no meal is due
- 3 cycles without recovery → IV glucose as below
| fast-acting, 15–20 g | longer-acting, after recovery |
|---|---|
| 150–200 mL fruit juice | normal carbohydrate-containing meal if due |
| ~150 mL regular (non-diet) soft drink | one slice of bread or toast |
| 3–4 glucose tablets (adjust to labelled carbohydrate) | two plain biscuits |
| 4 teaspoons / packets of sugar in water | a small sandwich |
| glucose gel by labelled carbohydrate | 200–300 mL milk |
- not chocolate or other high-fat food first: fat slows absorption
reduced consciousness, seizure or unsafe swallowing
- IV glucose and glucagon as in the box above; recheck at 10–15 min
- renal or cardiac failure → smallest volume, so glucose 20% or 50%
- glucagon works poorly when glycogen is depleted: prolonged fasting, malnutrition, heavy alcohol use, severe liver disease
sulfonylurea-associated hypoglycemia
- recurrence is the rule: IV glucose to correct, glucose 10% IV infusion if it recurs
- octreotide 50 mcg SC q6–8h with senior / toxicology advice
- risk persists 24–36 h, longer with renal impairment: monitor glucose for at least 24–48 h
- after recovery → reduce or hold the causative insulin or sulfonylurea, treat the cause, keep checking glucose
- hand over → cause, last glucose and time, next check due, escalation trigger
evidence
| source | type |
|---|---|
| ADA Standards of Care 2026 (hypoglycemia) | international guideline |
| Endocrine Society adrenal-insufficiency guidance | international guideline |
| JBDS 01: Hospital Management of Hypoglycaemia in Adults (Jan 2023) | international guideline |
Verify indication, dose, allergies, interactions, renal/hepatic function and local protocols before prescribing.
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reviewed 17 Aug 2026updated Oct 2026file vital/hypoglycemia