Tranexamic Acid (TXA) is a synthetic derivative of the amino acid lysine that inhibits fibrinolysis (clot breakdown) by blocking the lysine binding site on plasminogen, competitively inhibiting the activation of plasminogen to plasmin.

Hepatic metabolism with renal excretion.

  • Onset: Within minutes
  • Duration: 17 hours
  • Half-life: 3 hours
  • Significant trauma (< 3 hours) with signs of hypovolaemia or
  • Significant active haemorrhage that requires the use of
    • Tourniquet/s
    • Haemostatic/pressure dressing/s
  • Suspected head injury (< 3hours) with GCS motor score of 4 (withdrawing from pain) or below
  • Severe Primary or Secondary Post-Partum Haemorrhage (> 1000 mL) or PPH with signs of hypovolaemia (birth/bleed occurred < 3hrs)
  • Significant post-tonsillectomy haemorrhage
  • Known hypersensitivity to Tranexamic Acid.
  • Injury time more than 3 hours (associated with increase in mortality).
 Precautions / Notes
  • TXA administration in the traumatic patient in the metropolitan area should ordinarily prompt transport to a major trauma centre 
  • Rapid administration may lead to hypotension and dizziness.
  • Give as early as possible post event. Survival benefit is reduced by 10% for every fifteen minute delay with no benefit seen after 3 hours
  • Address critical interventions (airway management, control of major haemorrhage etc.) before administration of tranexamic acid.
  • Tranexamic acid administration should not delay transfer, noting it may be administered en route.
  • Safety during pregnancy has not been demonstrated, but the balance of risk is such that it should be administered if the indications are met in life threatening circumstances
 Weight-based Calculations
IV Tranexamic Acid for risk of significant bleeding (/mL)
Presentation: 1000mg:10mL
Calculated dose:  in

Adult IV / IO:

  • 1 g slowly over 10 minutes (Rapid administration may cause hypotension)

Paediatric (<12 years) IV / IO:

  • 15 mg/kg slowly over 10 minutes (max injection rate 50 mg/minute)
 Special Considerations
  • Hypotension (fast infusion rate)
  • Headache
  • Dizziness
  • Convulsions (lowers seizure threshold)
  • Nausea and/or vomiting
  • Diarrhoea
1 g Tranexamic Acid in 10 mL vial (100 mg/mL).


Current mode:
Extended Care:
Colour assist:


The CRASH-2 Collaborators (2010) Effects of Tranexamic acid on death, vascular occlusive events, and blood transfusion in trauma patients with significant haemorrhage (CRASH-2): a randomised, placebo-controlled trial. Lancet. 377. 9771: 1096

WOMAN Trial Collaborators. Effects of early tranexamic acid administration on mortality, hysterectomy, and other morbidities in woman with post-partum haemorrhage (WOMAN): an international, randomised, double blind, placebo-controlled trial. Lancet 2017: 389: 2105- 16

Morison JJ, Dubose JJ, Ramussen TE, et al Military application of tranexamic acid in trauma emergency resuscitation (MATTERs) study Ach Surg 2012; 147: 113-19

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