Hypoglycemia
ABCs
- capillary glucose now; do not delay treatment if symptomatic, seizing or unconscious
- unexpected or inconsistent → repeat, or lab glucose after starting treatment
- consciousness; protect airway if reduced; IV access
- levels
- level 1 → glucose < 3.9 and ≥ 3.0 mmol/L
- level 2 → glucose < 3.0 mmol/L
- level 3 → severe cognitive or physical impairment requiring assistance, regardless of measured glucose
reduced consciousness, seizure or unsafe swallowing
- call for help and protect airway
- IV glucose → 150–200 mL of 10% or 75–100 mL of 20% over 10–15 min; alternative glucose 50% 50 mL
- no IV access → glucagon 1 mg IM while obtaining access
- continue airway and ventilation support as needed
- recurrent or not maintaining → glucose 10% infusion, titrated to glucose
HPI
- symptoms
- autonomic → sweating, palpitations, tremor, nausea
- neuroglycopenic → confusion, behavioral change, focal deficits, seizures
- medication and cause review (once, here)
- diabetes type and treatment; timing and dose of latest insulin
- sulfonylurea or meglitinide use; recent dose changes
- missed meals, fasting or NPO status
- vomiting or diarrhea; alcohol use
- acute illness or infection; renal or hepatic deterioration
- weight loss, hypotension, steroid withdrawal, or features of adrenal insufficiency
workup
- repeat capillary glucose to confirm response
- electrolytes and renal function; liver tests
- infection screen if indicated; further tests guided by history
- adrenal insufficiency
- 8–9 AM cortisol ± ACTH if recurrent or unexplained and adrenal insufficiency suspected
- clues: hypotension, hyponatremia, hyperkalemia, weight loss, hyperpigmentation, recent glucocorticoid withdrawal
- one morning cortisol does not rule it out: interpretation is assay-dependent, indeterminate results may need ACTH stimulation testing
- suspected adrenal crisis → cortisol / ACTH before steroids only if no delay, then treat
- recurrent or unexplained hypoglycemia without diabetes
- critical sample during hypoglycemia, if it does not delay treatment
- lab plasma glucose, insulin, C-peptide, β-hydroxybutyrate, sulfonylurea / meglitinide screen; further tests per endocrinology
management
conscious and able to swallow
- give 15–20 g fast-acting carbohydrate
- recheck glucose after 10–15 min
- repeat, up to 3 cycles, if glucose remains < 4 mmol/L
- above 4 mmol/L, symptoms resolved → longer-acting carbohydrate if no meal immediately due
- keep monitoring: recurrence is common
| 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 |
- avoid chocolate, ice cream, and other high-fat foods initially: fat slows absorption
reduced consciousness, seizure or unsafe swallowing
- call for help, protect the airway
- airway and ventilation support as needed
- IV glucose over 10–15 min
- glucose 10% 150–200 mL
- or glucose 20% 75–100 mL
- alternative: glucose 50% 50 mL
- no IV access → glucagon 1 mg IM, keep working for access
- recheck glucose after 10–15 min
- recurrent or not maintaining
- glucose 10% infusion, titrated to glucose
- reassess the underlying cause
- use the smallest volume in renal or cardiac failure
- glucagon is less effective when glycogen stores are depleted
- prolonged fasting
- malnutrition
- heavy alcohol use
- severe liver disease
sulfonylurea-associated hypoglycemia
- recurrence is common: the glucagon response may be temporary
- IV glucose to correct, then a glucose infusion if it recurs
- octreotide 50 mcg SC q6–8h with senior / toxicology advice (available as 50 & 100 mcg/mL)
- recurrent hypoglycemia may persist 24–36 h, especially with renal impairment
- monitor glucose for at least 24–48 h
after stabilization
- adjust the causative therapy and treat the underlying cause
- continue glucose monitoring
escalation
escalate if
- persistent hypoglycemia after repeated treatment
- recurrent hypoglycemia or inability to maintain glucose
- ongoing seizure, reduced consciousness, or focal neurology after glucose correction
- suspected sulfonylurea or long-acting insulin overdose
- need for continuous IV glucose
- unexplained hypoglycemia without diabetes
- suspected adrenal crisis or other critical underlying illness
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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Last clinically reviewed · 17 August 2026 · Last updated · September 2026