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Drugs, Supplies and Delivery
Tranexamic Acid
Tranexamic acid is an antifibrinolytic agent used to prevent or treat excessive bleeding by inhibiting the breakdown of blood clots. It is widely utilized in conditions ranging from heavy menstrual bleeding to trauma and surgical prophylaxis. This article details its mechanism of action, uses, dosage, side effects, precautions, drug interactions, and generic names, referencing the British National Formulary (BNF), Lippincott Textbook of Pharmacology, and Lange Basic & Clinical Pharmacology.
Tranexamic acid competitively inhibits the activation of plasminogen to plasmin, an enzyme that degrades fibrin clots. By binding to plasminogen, it blocks the interaction with fibrin, stabilizing clots and reducing bleeding. Unlike other antifibrinolytics, it does not affect thrombin generation, preserving normal hemostasis (Lippincott Textbook of Pharmacology).
- Menorrhagia (Heavy Menstrual Bleeding):
- First-line treatment to reduce blood loss (BNF).
- Traumatic or Surgical Bleeding:
- Used in trauma (e.g., postpartum hemorrhage, traumatic hyphema) and perioperatively (e.g., cardiac, orthopedic surgeries) to minimize blood loss.
- Hereditary Angioedema:
- Prophylaxis and treatment of acute attacks (Lange Basic & Clinical Pharmacology).
- Dental Procedures in Hemophilia Patients:
- Reduces bleeding risk during tooth extraction.
Dosing varies by indication and route:
- Menorrhagia:
- Oral: 1 g (two 500 mg tablets) three times daily for up to 4 days during menstruation.
- Surgical Prophylaxis:
- IV: 1 g preoperatively, repeated every 8 hours if needed.
- Topical: 5% solution applied to bleeding surfaces.
- Trauma (e.g., Postpartum Hemorrhage):
- IV: 1 g over 10 minutes, repeated if bleeding persists (BNF).
Renal Impairment:
- Reduce dose by 50% if CrCl 50–80 mL/min; avoid if CrCl <50 mL/min (IV) or <30 mL/min (oral).
- Common:
- Gastrointestinal disturbances (nausea, diarrhea).
- Headache, fatigue, or visual disturbances (reversible with discontinuation).
- Serious:
- Thromboembolic Events: DVT, PE, or stroke (rare but significant).
- Seizures (with high IV doses or renal impairment).
- Allergic reactions (e.g., rash, anaphylaxis) (Lippincott Textbook of Pharmacology).
- Absolute Contraindications:
- Active thromboembolic disease (e.g., DVT, stroke).
- Hypersensitivity to tranexamic acid.
- Relative Contraindications:
- History of thrombosis or thromboembolic risk factors.
- Severe renal impairment.
- Pregnancy/Lactation:
- Safe in pregnancy; limited excretion in breast milk (BNF).
- Anticoagulants (e.g., warfarin, heparin): May counteract efficacy.
- Combined Hormonal Contraceptives: Potential additive thrombosis risk.
Thrombolytics (e.g., alteplase): Contraindicated due to opposing mechanisms
- Generic Name: Tranexamic acid.
- Brand Names: Cyklokapron (IV/global), Lysteda (oral/US), Tranex (oral/UK).
