1. Clinical Overview
Tranexamic Acid is a synthetic lysine analogue antifibrinolytic agent. It competitively inhibits the activation of plasminogen to plasmin, thereby preventing the degradation of fibrin clots. It is a cornerstone therapy for the management and prevention of excessive bleeding across various clinical scenarios in India, particularly in obstetrics, trauma, and surgery.
| Onset | Duration | Bioavailability |
|---|---|---|
| Oral: Peak plasma concentrations reached in approximately 2-3 hours. Clinical hemostatic effect begins as plasma levels rise. | The plasma half-life is about 2-3 hours, but the antifibrinolytic effect in tissues (e.g., endometrium, urinary tract) can persist for up to 17-18 hours due to high affinity for plasminogen. | Approximately 30-40% following oral administration. |
2. Mechanism of Action
Tranexamic acid is a competitive inhibitor of plasminogen activation. It binds reversibly to the lysine-binding sites on plasminogen, blocking its interaction with fibrin. This prevents the conversion of plasminogen to plasmin, the enzyme responsible for breaking down fibrin clots, fibrinogen, and other plasma proteins.
3. Indications & Uses
- Heavy Menstrual Bleeding (Menorrhagia)
- Prevention and treatment of hemorrhage in hemophilia patients undergoing dental extraction
- Traumatic Hyphaema (to prevent secondary bleeding)
4. Dosage & Administration
Adult Dosage: **Heavy Menstrual Bleeding:** 650mg to 1300mg orally two to three times daily for 3-5 days during menstruation. **General Hemostasis:** 650mg to 1500mg orally two to three times daily. Duration depends on indication.
Administration: Tablet should be swallowed whole with a full glass of water, with or after food to minimize gastrointestinal upset. For menstrual bleeding, start at the onset of heavy flow.
5. Side Effects
Common side effects may include:
- Nausea
- Vomiting
- Diarrhea
- Abdominal pain
- Headache
6. Drug Interactions
| Drug | Effect | Severity |
|---|---|---|
| Combined Hormonal Contraceptives (Pills) | Additive risk of thromboembolic events. | Major |
| Factor IX Complex Concentrates / Anti-inhibitor Coagulant Concentrates | Increased risk of thrombosis. | Major |
| Tretinoin (All-Trans Retinoic Acid) for APL | Increased risk of thrombosis. | Major |
| Other Antifibrinolytics (e.g., Aminocaproic Acid) | Additive effects, increased risk of side effects. | Moderate |
| Medications affecting renal function (e.g., NSAIDs, Aminoglycosides) | May reduce excretion, increasing tranexamic acid levels and toxicity risk. | Moderate |
7. Patient Counselling
- DO take the tablet exactly as prescribed, with food if stomach upset occurs.
- DO report any signs of blood clots immediately: sudden shortness of breath, chest pain, leg pain/swelling, sudden severe headache, vision/speech problems.
- DO inform all your doctors and dentists you are taking this medicine before any procedure.
- DONT take it if you are pregnant, planning pregnancy, or breastfeeding without consulting your doctor.
- DONT crush or chew the tablet.
8. Toxicology & Storage
Overdose: Nausea, vomiting, hypotension, orthostatic symptoms, dizziness, headache, mental status changes, and severe cases may lead to thromboembolic events or seizures.
Storage: Store below 30°C in a cool, dry place, protected from light and moisture. Keep out of reach of children.