Liverpool Hospital Emergency Department


  • Bleeding and over-anticoagulation from Unfractionated heparin 
  • Reversal of Heparin anticoagulation after renal dialysis, before surgery, after open  heart surgery.
  • Potential reversal of low molecular weight heparin in haemorrhage situations.


  • 50mg/5mL ampoules (10mg/ml) 

Dosage and Administration 

  • Heparin anticoagulation reversal: (1mg per 100units of heparin) 
  • Dilute 100mg in 100mL sodium chloride 0.9% or 5% dextrose and infuse over  1 hour

  • Heparin overdose:
    • (1mg per 100units of heparin)
    • Dilute 50mg in 100mL sodium chloride 0.9% and infuse over 1-hour 
    • Dosing should be correlated with APTT and clinical evidence of bleeding with  heparin overdose
  • Enoxaparin Reversal:
    • Administer 1 mg of protamine sulfate for every 1 mg of enoxaparin  administered in the previous 8 hours.
  • Heparin is continuously excreted; thus, dosage is to be reduced if more than  15minutes have elapsed since the heparin injection.
  • In a situation where rapid reversal is necessary a slow IV injection over 10 mins is  acceptable. 

Side Effects 

  • Hypotension, flushing, pulmonary oedema and bradycardia 

Pit Falls 

  • Contraindicated: Allergy to protamine sulphate and/or fish.
  • At high concentrations, Protamine will act as an anticoagulant. 
  • Not recommended for danaparoid overdose.