Tranexamic Acid Dosing Per Kilogram
The recommended dose of tranexamic acid is 10 mg/kg IV as a loading dose, followed by a maintenance infusion of 1-5 mg/kg/hour, with the specific regimen tailored to the clinical indication. 1
Standard Weight-Based Dosing
Loading Dose
- Administer 10 mg/kg IV as a single bolus dose for most indications including trauma, surgery, and bleeding disorders 1
- The FDA-approved dosing for hemophilia patients undergoing dental procedures is 10 mg/kg actual body weight administered immediately before the procedure 1
- Infuse no faster than 1 mL/minute to avoid hypotension 1
Maintenance Infusion
- Continue with 1-5 mg/kg/hour IV infusion after the loading dose 2, 3
- The lower end (1 mg/kg/hour) achieves therapeutic plasma levels of 10 μg/mL required to inhibit fibrinolysis, as demonstrated by the Horrow regimen 2, 3
- For trauma patients, European guidelines recommend 10-15 mg/kg loading dose followed by 1-5 mg/kg/hour maintenance 2
Context-Specific Dosing Algorithms
For Major Trauma/Hemorrhagic Shock
Use the CRASH-2 fixed-dose protocol instead of weight-based dosing:
- 1 gram IV over 10 minutes (loading dose) 3
- Followed by 1 gram IV infusion over 8 hours (maintenance) 3
- Must be administered within 3 hours of injury for mortality benefit 3
- This fixed-dose regimen demonstrated 9% relative risk reduction in all-cause mortality 3
For Cardiac Surgery
- Loading dose: 10 mg/kg IV bolus 3
- Maintenance: 1 mg/kg/hour continuous infusion 3
- Maximum total dose: 100 mg/kg to avoid seizure risk, particularly in patients over 50 years 3, 4
For Dental Procedures in Hemophilia
- 10 mg/kg IV immediately before tooth extraction 1
- Post-extraction: 10 mg/kg IV 3-4 times daily for 2-8 days 1
For Hereditary Hemorrhagic Telangiectasia (Epistaxis/GI Bleeding)
Oral dosing regimen (not IV):
- Start at 500 mg twice daily 2
- Gradually increase up to 1000 mg four times daily or 1500 mg three times daily 2
- Contraindications include recent thrombosis; relative contraindications include atrial fibrillation or known thrombophilia 2
Dose Adjustments for Renal Impairment
Mandatory dose reduction based on serum creatinine: 1
| Serum Creatinine | Recommended Dosing |
|---|---|
| 1.36-2.83 mg/dL (120-250 μmol/L) | 10 mg/kg twice daily |
| 2.83-5.66 mg/dL (250-500 μmol/L) | 10 mg/kg once daily |
| >5.66 mg/dL (>500 μmol/L) | 10 mg/kg every 48 hours OR 5 mg/kg every 24 hours |
- These reductions apply to all doses, both loading and maintenance 1
- Recent pharmacokinetic data suggests 5 mg/kg/hour maintenance infusion for poor renal function (eGFR <60) versus 7.5 mg/kg/hour for good renal function 5
Alternative Dosing Considerations
Intramuscular Administration
- 30 mg/kg IM achieves serum concentrations comparable to IV administration 6
- The standard 15 mg/kg IM dose is insufficient; doubling to 30 mg/kg is necessary 6
- Useful in low-resource or military settings where IV access is limited 6
- Distributing the dose between two injection sites does not affect drug uptake 6
Weight-Based vs. Fixed-Dose
- Weight-based dosing (20 mg/kg/hour) significantly reduces postoperative blood loss compared to fixed 1-gram doses in revision knee arthroplasty 7
- Weight-based regimens are superior for optimizing anti-fibrinolytic effect while avoiding excessive dosing 5
Duration and Monitoring
- Continue infusion until bleeding is adequately controlled, typically 8 hours for trauma following CRASH-2 protocol 2, 3
- Discontinue as soon as hemostasis is achieved to minimize thrombotic complications 2
- Antifibrinolytic therapy should be guided by thrombelastometric monitoring when available 2, 8
Critical Safety Warnings
Absolute Contraindications
- Active intravascular clotting 1
- Subarachnoid hemorrhage (risk of cerebral edema and infarction) 1
- Hypersensitivity to tranexamic acid 1
Thromboembolic Risk
- Avoid concomitant use with pro-thrombotic agents including Factor IX concentrates, anti-inhibitor coagulant concentrates, and hormonal contraceptives 1
- Increased thrombotic risk when combined with oral contraceptives 8
Route-Specific Risks
- IV administration only—never intrathecal 1
- Inadvertent intrathecal administration causes seizures and cardiac arrhythmias 1