Tranexamic acid
trans-4-(Aminomethyl)cyclohexanecarboxylic acid
Also known as: Cyklokapron · TXA · Acidum tranexamicum
Reviewed by the VetSheet Veterinary TeamUpdated Apr 5, 2026Evidence-based veterinary reference
Dosing by species
Dosing data for this drug is not yet available in the VetSheet formulary. Every other section below is complete. Consult the current product label before prescribing.
Overview
Tranexamic acid is a synthetic lysine analogue used as an antifibrinolytic to control bleeding. It is particularly beneficial in patients with hyperfibrinolytic conditions and certain forms of coagulopathy.
Clinical Pearl: Commonly used in veterinary medicine for trauma, surgical bleeding (e.g., greyhound surgeries), and bleeding associated with Angiostrongylus vasorum (lungworm) or immune-mediated thrombocytopenia (IMTP).
Warning: Use with caution in patients with renal impairment or pre-existing thromboembolic disease.
Mechanism of action
Tranexamic acid is a synthetic lysine analogue that reversibly binds to the lysine binding sites of plasminogen.
Plasminogen → (blocked by TXA) → Plasmin
This prevents the action of plasmin on fibrin, thereby delaying fibrin dissolution (fibrinolysis) and reducing bleeding. By stabilizing the clot, it helps maintain hemostasis in bleeding disorders.
Safety & warnings
Contraindications
- Disseminated intravascular coagulation (DIC)
- Thromboembolic disease
- Severe renal impairment (without dose adjustment)
Adverse effects
- Gastrointestinal upset (vomiting, diarrhea)
- Hypotension (if given rapidly IV)
- Seizures (at high doses)
- Retinal changes (rare, high doses)
Precautions
Administer IV injections slowly to prevent hypotension and vomiting. Dose reduction is required in patients with renal impairment as the drug is primarily excreted unchanged in the urine.
Drug interactions
Increased risk of thrombosis
Antagonizes fibrinolytic effects
Monitoring
- Clinical signs of bleeding
- Coagulation profiles (PT, aPTT, TEG/ROTEM)
- Renal function
Pharmacokinetics
Half-life
Absorption
Rapidly absorbed after oral administration, though bioavailability is moderate (~30-50%).
Distribution
Widely distributed throughout the body. Crosses the placenta and blood-brain barrier.
Metabolism
Minimal hepatic metabolism.
Elimination
Primarily excreted unchanged in the urine via glomerular filtration.
Overdose
Overdosage may result in severe gastrointestinal signs (vomiting, diarrhea), hypotension, and neurological signs including seizures (due to GABA-A receptor antagonism). Treatment is symptomatic and supportive.
Available products
Formulations
- Injectable: 500 mg/5 ml solution for injection ampoules
- Oral: 500 mg tablets
Human-labeled
- Cyklokapron 500 mg/5 ml solution for injection
- Cyklokapron 500 mg tablets
Regulatory status
Human approved products used off-label in veterinary medicine.
POM (Prescription Only Medicine)
POM (Prescription Only Medicine)
No regulatory data for: 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
Storage & stability
Store at room temperature (15-30°C). Protect from light and freezing.
Client information
Tranexamic acid is prescribed to help stop or prevent excessive bleeding by stabilizing blood clots.
- Administration: Can be given with or without food. If vomiting occurs, try giving with a small meal.
- Side Effects: Watch for stomach upset.
Contact your veterinarian immediately if you notice sudden weakness, difficulty breathing, or seizures.
VetSheet drug reference is intended for licensed veterinary professionals as a clinical decision-support aid, not a substitute for professional judgement or the manufacturer’s current label.