Tranexamic acid

Tranexamic acid (commonly marketed as Cyklokapron in the U.S. and as Transamin in Asia) is often prescribed for excessive bleeding. It is an antifibrinolytic that competitively inhibits the activation of plasminogen to plasmin, a molecule responsible for the degradation of fibrin. Fibrin is the basic framework for the formation of a blood clot in hemostasis. It has roughly 8 times the antifibrinolytic activity of an older analogue, ε-aminoacaproic acid.

Menstrual bleeding
Tranexamic acid (cyklokapron, transamin) is a synthetic derivative of the amino acid lysine. It exerts its antifibrinolytic effect through the reversible blockade of lysine binding sites on plasminogen molecules. It inhibits endometrial plasminogen activator and thus prevents fibrinolysis and the breakdown of clot. Side effects are uncommon. While prolonged treatment may heighten the risk of an increased thrombotic tendency, such as deep vein thrombosis, large scale studies reveal that the incidence of thrombosis in women treated by tranexamic acid is no different from the spontaneous incidence of thrombosis in women.

Tranexamic acid is used as firstline nonhormonal treatment of dysfunctional uterine bleeding, and heavy bleeding associated with uterine fibroids. A recent study showed that patients treated with tranexamic acid are more likely to develop thrombosis and necrosis in their fibroids, and may result in pain and fever. Moreover, the histological appearance of the necrosis in these drug-related fibroids may be mistaken for smooth muscle tumors of uncertain malignant potential.

Haemophilia
Tranexamic acid is also useful in the treatment of bleeding as a second line treatment next to factor VIII in haemophilia patients (i.e. Tooth extraction in haemophilia patients.)

Angioedema
In acquired angioedema types I and II and non-histaminergic angioedema, antifibrinolytics such as tranexamic acid or ε-aminocaproic acid may be effective.

Cardiac surgery
Tranexamic acid is used in cardiac surgery, e.g. coronary artery bypass surgery, to prevent excessive blood loss.

Orthopedic Surgery
Tranexamic acid is used in orthopedic surgery to reduce bloodloss. It is of proven value in clearing the field of surgery and reducing per and postoperative blood loss. Drain and number of transfusion is reduced. However the hidden blood loss is not reduced. Still it is becoming an important tool in the anaesthetist's arsenal. It is commonly used in joint replacement surgery.

Additional Resources

 * Tranexamic acid (Dr. P.L.F. Giangrande, Oxford Haemophilia Centre)
 * Tranexamic acid (UK patient information leaflet)
 * Types of Angioedema and treatments (Hereditary Angioedema Association)

Tranexamsäure Ácido tranexámico Acide tranexamique Acido tranexamico トラネキサム酸 Kwas traneksamowy