Tranexamic Acid (TXA) | Medication Reference

Bedside Snapshot

Core Use: Major trauma hemorrhage (CRASH-2 protocol), postpartum hemorrhage (WOMAN trial), and selected perioperative bleeding; synthetic lysine analogue that inhibits fibrinolysis
Standard Adult Trauma Dose: 1 g IV over 10 minutes, then 1 g IV over 8 hours (many EMS systems give single 1 g bolus)
Timing Critical: Maximum benefit when given within 1 hour of bleeding onset; benefit diminishes and potential harm increases when given >3 hours after trauma or childbirth
Key Danger: Renally cleared; accumulation increases risk of seizures and thrombotic events at high/repeated doses, especially in renal impairment
Special Note: NOT a substitute for blood products, source control, or balanced resuscitation—it's an adjunct that preserves existing clots by preventing fibrinolysis

Brand & Generic Names

Generic Name: Tranexamic acid
Brand Names: Cyklokapron, Lysteda (PO), various generics

Medication Class

Antifibrinolytic; synthetic lysine analogue; plasminogen activation inhibitor

Pharmacology

Mechanism of Action:

Tranexamic acid is a synthetic analogue of lysine that competitively inhibits the activation of plasminogen to plasmin by blocking lysine-binding sites on plasminogen and plasmin
By inhibiting plasmin formation and activity, TXA stabilizes fibrin clots and reduces fibrinolysis, decreasing ongoing bleeding without directly affecting coagulation factor generation
Does not promote new clot formation but preserves existing clots; however, by tipping the balance away from fibrinolysis, it can theoretically increase risk of thrombosis in patients with strong prothrombotic tendencies

Pharmacokinetics:

Onset: Antifibrinolytic effect begins within minutes of IV administration
Bioavailability (PO): ~30–50%; peak plasma levels in 2–3 hours with oral dosing
Distribution: Volume of distribution ~9–12 L; crosses placenta and appears in breast milk at low levels
Metabolism: Minimal; TXA is largely unchanged in circulation
Elimination: Primarily renal excretion; half-life ~2–3 hours in normal renal function, prolonged in renal impairment

Dosing & Administration

Available Forms:

IV solution: commonly 100 mg/mL (e.g., 1 g in 10 mL vials); may be further diluted in 0.9% NaCl or D5W for infusion
Oral tablets: typically 650 mg (Lysteda), 500 mg or 1 g tablets in some regions
Topical/nebulized (off-label): IV formulation applied to gauze or diluted in saline for epistaxis or hemoptysis

Dosing – Tranexamic Acid (Adult; always follow local protocol):

Indication / Scenario	Dose & Route	Frequency / Timing	Notes
Trauma hemorrhage – hospital regimen (CRASH-2)	1 g IV over 10 min, then 1 g IV over 8 h	Start ASAP, within 3 h of injury	Do not start >3 h after injury (possible harm); prefer within 1 h
Trauma hemorrhage – EMS/prehospital	1 g IV or IO over ~10 min	Single bolus en route	Infusion completed in hospital; follow regional protocol
Postpartum hemorrhage (PPH)	1 g IV over 10 min	Give ASAP once PPH diagnosed, within 3 h of birth	May repeat once after 30 min if bleeding persists; max commonly 2 g/24 h
Perioperative bleeding	10–15 mg/kg IV before incision	May repeat intra-op or use infusion 1–5 mg/kg/h	Specific dosing varies by surgical service and procedure
Epistaxis (topical; off-label)	500–1000 mg TXA in 5–10 mL applied to gauze	Held in nostril 10–15 min; may repeat	Often combined with compression/packing
Hemoptysis (nebulized; off-label)	500–1000 mg in 5–10 mL NS via nebulizer	Every 6–8 h as needed, short course	Evidence limited; institutional protocols vary
Renal impairment (CrCl <30 mL/min)	Reduce dose or extend interval (e.g., 50% dose)	Individualize based on indication	Higher risk of accumulation, seizures, and thrombosis

Contraindications

Contraindications:

Active intravascular clotting (e.g., acute DVT, PE, or active arterial thrombosis) unless benefits clearly outweigh risks
History of TXA hypersensitivity or anaphylaxis
Subarachnoid hemorrhage (risk of cerebral ischemia in older data)

Major Precautions:

History of thromboembolic disease (DVT, PE, MI, stroke): use only when strong indication and in consultation with senior/hematology when possible
Renal impairment: reduced clearance increases TXA levels; lower doses or extended intervals are required
High-dose IV regimens have been associated with increased seizure risk; avoid unnecessarily high doses
Hematuria from upper urinary tract (e.g., renal bleeding): risk of obstructive clots; use with caution or avoid

Adverse Effects

Common:

Nausea, vomiting, diarrhea
Dizziness, fatigue
Nasal irritation or cough with nebulized/topical use

Serious:

Venous thromboembolism (DVT, PE), arterial thrombosis (MI, stroke) – low absolute risk in most large trauma/PPH trials but possible in high-risk patients
Seizures, particularly with high total doses, rapid IV administration, or in cardiac surgery settings
Hypotension with rapid IV push (especially if given undiluted); recommended to infuse over 10 minutes
Anaphylaxis or severe hypersensitivity reactions (rare)

Special Populations

Renal Impairment:

Reduced clearance; dose reduction required in CrCl <30 mL/min
Higher risk of accumulation leading to seizures and thrombotic events

Pregnancy & Lactation:

Used in postpartum hemorrhage within 3 hours of delivery (WOMAN trial)
Crosses placenta and appears in breast milk at low levels; considered acceptable when benefits outweigh risks

Elderly:

May have reduced renal function; consider dose adjustments
Monitor closely for thrombotic events

Monitoring

Clinical control of bleeding (vital signs, visible bleeding, transfusion requirements)
Hemoglobin/hematocrit and coagulation labs as part of broader hemorrhage management
Signs and symptoms of thromboembolism (leg swelling, chest pain, hypoxia, neurologic deficits), especially in patients with pre-existing risk factors
Renal function (serum creatinine, urine output), particularly with repeated or high-dose regimens
Neurologic status for new-onset seizures or focal deficits after TXA exposure

Indications / Clinical Uses (ED/ICU/EMS)

Suspected or confirmed significant traumatic hemorrhage in adults (and pediatrics per local protocol), particularly in patients with systolic hypotension, tachycardia, or signs of ongoing bleeding, when presentation is within 3 hours of injury
Postpartum hemorrhage (PPH) due to uterine atony, trauma, or other obstetric causes, administered as soon as PPH is diagnosed and within 3 hours of birth
Perioperative bleeding reduction in high-risk surgeries (e.g., orthopedic, cardiac, liver transplantation, major spine surgery) under anesthesia/surgical protocols
Selected mucosal bleeding: epistaxis (topical TXA on packing) and hemoptysis (nebulized or endobronchial TXA) as adjunctive therapy in some institutions

Clinical Pearls

Time is Hemostasis: For trauma and PPH, the earlier TXA is given (ideally within 1 hour), the better the mortality signal; avoid initiating TXA more than 3 hours after onset.

EMS High-Yield Intervention: In EMS trauma care, a single 1 g IV/IO bolus of TXA for hypotension or significant bleeding en route is a high-yield, low-complexity intervention that hands off seamlessly to hospital infusion protocols.

Adjunct Not Substitute: TXA is not a substitute for blood, source control, or balanced resuscitation; it is an adjunct to good trauma/obstetric care, not a standalone fix.

Thrombotic History: When considering TXA in patients with a strong thrombotic history, weigh indication severity and timing carefully; in life-threatening hemorrhage, TXA is often still appropriate but document the risk–benefit reasoning.

Hemoptysis Use: For nebulized TXA in hemoptysis, ensure you're also working up and treating the underlying cause (PE, malignancy, bronchiectasis, infection) and involve pulmonology/interventional radiology early in major bleeds.

References

1. CRASH-2 trial collaborators. (2010). The importance of early treatment with tranexamic acid in bleeding trauma patients: An exploratory analysis of the CRASH-2 randomized controlled trial. The Lancet, 377(9771), 1096–1101.
2. WOMAN Trial Collaborators. (2017). Effect of early tranexamic acid administration on mortality, hysterectomy, and other morbidities in women with post-partum haemorrhage (WOMAN): An international, randomized, double-blind, placebo-controlled trial. The Lancet, 389(10084), 2105–2116.
3. HALT-IT Trial Collaborators. (2020). Effects of a high-dose 24-hour infusion of tranexamic acid on death and thromboembolic events in patients with acute gastrointestinal bleeding (HALT-IT). The Lancet, 395(10241), 1927–1936.
4. Lexicomp. (2025). Tranexamic acid: Drug information. Wolters Kluwer.
5. EMCrit Project. (2023). Antifibrinolytics & TXA in critical care. https://emcrit.org/