ClinCalc Pro
Menu
Calculators Drugs Pathways AI Dx Donate Get the App
Antidiabetic — Insulin Pregnancy: Insulin is the preferred treatment for diabetes in pregnancy

Insulin (various)

Brand names: NovoRapid (aspart), Humalog (lispro), Lantus (glargine), Actrapid (soluble)

Adult dose

Dose: DKA: 0.1 units/kg/hr IV infusion after fluid resuscitation
Route: IV infusion (DKA) / Subcutaneous (maintenance)
Frequency: Continuous infusion (DKA); multiple daily injections (maintenance)
Max: Individualised
ISPAD and NICE NG18 DKA protocol: Start insulin only after fluid resuscitation. Fixed rate insulin infusion (FRII)

Paediatric dose

Dose: DKA: 0.05-0.1 units/kg/hr IV. Maintenance: 0.5-1 unit/kg/day SC units/kg
Route: IV infusion (DKA) / Subcutaneous
Frequency: Continuous IV (DKA); multiple daily injections (maintenance)
Max: Individualised to blood glucose targets
DKA: Do not start insulin until after initial IV fluids — risk of cerebral oedema. BSPED 2020: use 0.05 units/kg/hr in younger or smaller children. Target glucose fall: 3-5 mmol/L/hour. Add dextrose to IV fluid when BG under 14 mmol/L. Maintenance: total daily dose approximately 0.5 units/kg/day pre-pubertal; 0.7-1 unit/kg/day pubertal

Dose adjustments

Renal

Reduce dose — insulin clearance reduced in renal impairment

Hepatic

Monitor closely — hepatic gluconeogenesis impaired

Paediatric weight-based calculator

DKA: Do not start insulin until after initial IV fluids — risk of cerebral oedema. BSPED 2020: use 0.05 units/kg/hr in younger or smaller children. Target glucose fall: 3-5 mmol/L/hour. Add dextrose to IV fluid when BG under 14 mmol/L. Maintenance: total daily dose approximately 0.5 units/kg/day pre-pubertal; 0.7-1 unit/kg/day pubertal

Clinical pearls

  • Cerebral oedema is the most feared DKA complication in children — headache, decreased consciousness, bradycardia, hypertension after initial improvement; treat with IV mannitol or hypertonic saline
  • BSPED 2020 DKA guideline: mandatory electrolyte monitoring; potassium replacement from start of insulin infusion
  • Insulin drives K into cells — always check K before starting insulin; hold insulin if K under 3.5 mmol/L until replaced
  • Type 1 DM: insulin is life-sustaining — never withhold; sick day rules essential education for parents
  • NPSA alert: write 'units' in full — never abbreviate as 'u' to prevent tenfold dosing errors

Contraindications

  • Hypoglycaemia

Side effects

  • Hypoglycaemia
  • Hypokalaemia (drives K into cells)
  • Cerebral oedema (DKA — risk if osmolality falls too rapidly)
  • Lipohypertrophy at injection site
  • Weight gain

Interactions

  • Beta-blockers (mask hypoglycaemia symptoms)
  • Salbutamol / terbutaline (cause hypokalaemia)
  • Corticosteroids (raise blood glucose)
  • ACE inhibitors (increase insulin sensitivity)

Monitoring

  • Blood glucose hourly (DKA)
  • Electrolytes (K, Na, phosphate)
  • pH and bicarbonate (DKA resolution)
  • Ketones (blood or urine)
  • Neurological observations (cerebral oedema watch)

Reference: BNF for Children; BSPED DKA Guidelines 2020; ISPAD Guidelines 2022; NICE NG18. Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

Calculators
Pathways