Prothrombin
Prothrombin (also known as Factor II) is a protein naturally produced by the liver that plays a critical role in the blood clotting cascade. As a medication, it may be administered in concentrated form to support clotting in patients with deficiencies or to reverse anticoagulant effects.
Prothrombin is a clotting factor protein used to support blood coagulation in patients with bleeding disorders or those on anticoagulant therapy.
Key facts at a glance
- RxNorm
- 1441688
- Generic
- Prothrombin
- Class
- unclassified
- Brands
- Kcentra, Balfaxar
- Availability
- rx
- Lactation
- unknown
- Routes
- —
- Forms
- injection
- Regions
- US, EU, CN, JP
- Monitoring
- —
This page is for informational purposes only.
Do not use this information to diagnose yourself or to replace a physician's advice. Always consult a qualified healthcare provider before starting, stopping, or changing any medication. If you believe you are experiencing a medical emergency, call your local emergency number immediately.
Used for management of bleeding disorders related to prothrombin deficiency, reversal of vitamin K antagonist anticoagulation (such as warfarin), and in emergency hemorrhage situations where rapid correction of clotting factors is needed.
Prothrombin is converted to thrombin during the coagulation cascade, which then converts fibrinogen to fibrin to form blood clots. Administration of exogenous prothrombin provides the necessary clotting factor to restore normal hemostasis.
Must be administered under medical supervision with appropriate monitoring. Potential risks include thromboembolic complications. May interact with anticoagulant medications. Not typically used as a routine supplement in patients with normal clotting function.
Official drug label
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This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 31, 2026. · Read our editorial policy