Maximum Dose for Tranexamic Acid
The maximum safe total dose of tranexamic acid is 100 mg/kg, with doses exceeding this threshold associated with significantly increased seizure risk, particularly in cardiac surgery patients over 50 years of age. 1, 2
Context-Specific Maximum Dosing
Cardiac Surgery (Highest Dose Setting)
- Maximum total dose: 100 mg/kg to avoid neurotoxicity and seizure complications 1, 2, 3
- The recommended high-dose regimen is 50-100 mg/kg IV over 30 minutes after induction of anaesthesia 1
- Alternative high-dose protocol: 30 mg/kg bolus + 16 mg/kg/h infusion + 2 mg/kg priming dose 3
- Doses exceeding 100 mg/kg total are associated with significantly increased seizure risk 2, 3
Major Trauma and Postpartum Hemorrhage (Standard Fixed Dosing)
- Maximum total dose: 2 grams administered as 1 g loading dose over 10 minutes, followed by 1 g infusion over 8 hours 1
- A second 1 g dose may be given if bleeding continues after 30 minutes or restarts within 24 hours (postpartum hemorrhage only), bringing the maximum to 2 grams total 1
- Must be administered within 3 hours of injury/birth for mortality benefit; administration beyond 3 hours is potentially harmful 1
Non-Cardiac Surgery
- Maximum: 2 grams administered as 1 g IV over 10 minutes prior to skin incision and 1 g at end of surgery 1
Pediatric Populations
- Maximum single dose: 1 gram (15 mg/kg, capped at 1 g) over 10 minutes, followed by 2 mg/kg/h infusion 1
Critical Safety Thresholds
Renal Impairment Dose Adjustments
The FDA label provides specific maximum dosing for renal dysfunction: 4
- Serum creatinine 1.36-2.83 mg/dL: Maximum 10 mg/kg twice daily
- Serum creatinine 2.83-5.66 mg/dL: Maximum 10 mg/kg once daily
- Serum creatinine >5.66 mg/dL: Maximum 10 mg/kg every 48 hours OR 5 mg/kg every 24 hours
Infusion Rate Limitation
- Maximum infusion rate: 1 mL/minute (100 mg/minute) to avoid hypotension 4
Important Caveats
Seizure Risk
- The seizure risk is dose-dependent, with greatest risk at higher doses, particularly in cardiac surgery patients over 50 years 2, 3
- One analysis showed tranexamic acid use as a very strong independent predictor of postoperative seizure (odds ratio = 14.3) 3
Absolute Contraindications to Any Dose
- Active intravascular clotting 4
- Subarachnoid hemorrhage (risk of cerebral edema and infarction) 4
- Known hypersensitivity to tranexamic acid 5, 4
Route-Specific Warning
- Tranexamic acid injection is for intravenous use only; intrathecal administration has caused serious adverse reactions including seizures and cardiac arrhythmias 4