What is the recommended intravenous dose of tranexamic acid (TXA) for a patient with heavy bleeding?

Tranexamic Acid Dosing for Heavy Bleeding

For acute heavy bleeding (trauma, postpartum hemorrhage), administer tranexamic acid 1 g IV over 10 minutes as a loading dose, followed by 1 g IV infused over 8 hours. 1, 2

Standard Dosing Protocol

The evidence-based regimen for life-threatening hemorrhage is:

• Loading dose: 1 g IV over 10 minutes 3, 1, 2
• Maintenance dose: 1 g IV infused over 8 hours 3, 1, 2
• Maximum infusion rate: No more than 1 mL/minute to avoid hypotension 4

This dosing is supported by the landmark CRASH-2 trial and has been adopted by multiple international guidelines for trauma-related hemorrhage. 3, 2

Critical Timing Considerations

Administer as early as possible and within 3 hours of injury or bleeding onset. 1, 5

• Effectiveness decreases by 10% for every 15-minute delay 1, 5
• Administration within 1 hour significantly reduces mortality due to bleeding 1
• Administration after 3 hours may paradoxically increase risk of death due to bleeding 1, 5
• Pre-hospital administration should be considered to ensure early treatment 1

Alternative Weight-Based Dosing

For certain populations, weight-based dosing may be appropriate:

• Trauma patients: 15 mg/kg loading dose followed by 2 mg/kg/hour infusion 1
• Postpartum hemorrhage: Initial dose of 1 g for bleeding >500 mL vaginal delivery or >1000 mL cesarean 1
• Hemophilia patients (dental procedures): 10 mg/kg IV single dose before extraction, then 10 mg/kg 3-4 times daily for 2-8 days 4

Dose Adjustments for Renal Impairment

Reduce dosing in patients with renal dysfunction, as tranexamic acid is predominantly excreted unchanged by the kidneys: 3, 4

• Serum creatinine 1.36-2.83 mg/dL: 10 mg/kg twice daily 4
• Serum creatinine 2.83-5.66 mg/dL: 10 mg/kg once daily 4
• Serum creatinine >5.66 mg/dL: 10 mg/kg every 48 hours or 5 mg/kg every 24 hours 4

Safety Considerations and Maximum Dosing

Do not exceed a total dose of 100 mg/kg to reduce seizure risk, particularly in patients over 50 years of age. 1, 6

• Higher doses are associated with increased risk of seizures, especially in cardiac surgery patients 1, 5, 6
• Venous thromboembolic events (DVT/PE) may be increased with tranexamic acid use 7
• Avoid concomitant use with prothrombotic agents (Factor IX concentrates, hormonal contraceptives) 4

Absolute Contraindications

Do not administer tranexamic acid in the following situations: 4

• Active intravascular clotting 4
• Subarachnoid hemorrhage (risk of cerebral edema and infarction) 3, 4
• Severe hypersensitivity to tranexamic acid 4

Route of Administration

Intravenous administration is the only evidence-based and FDA-approved route for acute hemorrhage. 1, 8, 4

• Current guidelines do not include specific recommendations for intramuscular dosing 1, 8
• Intramuscular bioavailability is 105% but lacks clinical outcome data 9
• Never administer intrathecally—serious adverse reactions including seizures and cardiac arrhythmias have occurred with inadvertent neuraxial administration 4

Common Pitfalls to Avoid

• Delaying administration beyond 3 hours: This significantly reduces effectiveness and may increase mortality 1, 5
• Exceeding maximum dose: Doses above 100 mg/kg increase seizure risk 1, 6
• Using in ischemic stroke candidates for thrombolysis: This could counteract beneficial effects of thrombolytics 5
• Mixing with blood or penicillin-containing solutions: Tranexamic acid should not be mixed with these 4
• Failing to adjust for renal impairment: Repeat doses should be used with caution in renal dysfunction 3, 4