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Prothrombin complex

Generic name: prothrombin complex [ pro-THROM-bin-KOM-plex ]
Brand name: Kcentra
Dosage form: intravenous powder for injection (-)
Drug class: Anticoagulant reversal agents

Medically reviewed by on Feb 27, 2023. Written by Cerner Multum.

What is prothrombin complex?

Prothrombin complex is used to quickly reverse the effects of a blood-thinning medicine (such as warfarin) during a major bleeding episode, or when there is a need for emergency surgery or invasive medical procedure.

Prothrombin complex may also be used for purposes not listed in this medication guide.

Prothrombin complex side effects

Get emergency medical help if you have signs of an allergic reaction: hives, rash; nausea, vomiting, feeling light-headed; fast heartbeats; chest tightness, wheezing, difficult breathing; swelling of your face, lips, tongue, or throat.

Tell your caregivers right away if you have:

  • a light-headed feeling, like you might pass out;

  • chest pain or pressure, pain when you breathe, shortness of breath;

  • flushing (sudden warmth, redness, or tingly feeling);

  • low red blood cells (anemia)--pale skin, unusual tiredness, feeling light-headed or short of breath, cold hands and feet;

  • signs of a stroke--sudden numbness or weakness (especially on one side of the body), severe headache, slurred speech, balance problems;

  • signs of a blood clot in the lung--chest pain, sudden cough, wheezing, rapid breathing, coughing up blood; or

  • signs of a blood clot deep in the body--swelling or pain in your arms, legs, or stomach.

Common side effects of prothrombin complex may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.


Tell your doctor if you have ever had a heart attack, stroke, TIA or "mini-stroke", chest pain, severe circulation problems, or a blood clot (especially within the past 3 months).

While using prothrombin complex, tell your caregivers right away if you have signs of a blood clot: sudden numbness or weakness, problems with vision or speech, chest pain, cough, wheezing, rapid breathing, swelling or pain in your arms, legs, or stomach.

This medicine is for use in people who use blood thinners such as warfarin. After you are treated with prothrombin complex, do not start using your blood thinner again until your doctor tells you to.

Before taking this medicine

You should not be treated with this medicine if you have:

  • low levels of platelets in your blood after using heparin;

  • excessive blood-clotting caused by a condition called disseminated intravascular coagulation; or

  • a history of severe allergic reaction to prothrombin complex, Protein C or Protein S, Antithrombin III, heparin, human albumin, or Factors II, VII, IX, X.

If possible before you receive prothrombin complex, tell your caregivers if you have ever had:

  • a stroke, including TIA (transient ischemic attack) or "mini-stroke";

  • a heart attack;

  • disseminated intravascular coagulation;

  • severe circulation problems;

  • chest pain (angina); or

  • if you have had a blood-clot within the last 3 months.

Tell your doctor if you are pregnant or breastfeeding.

Prothrombin complex is made from donated human plasma and may contain viruses or other infectious agents. Donated plasma is tested and treated to reduce the risk of contamination, but there is still a small possibility it could transmit disease. Ask your doctor about any possible risk.

How is prothrombin complex given?

Prothrombin complex is given as an infusion into a vein. A healthcare provider will give you this injection.

After you are treated with prothrombin complex, do not start using your blood thinner again until your doctor tells you to.

In case of emergency, wear or carry medical identification to let others know you use a blood thinner.

Prothrombin complex dosing information

Usual Adult Dose for Reversal of Acquired Coagulation Factor Deficiency:

INR 2 to less than 4: 25 units of Factor IX/kg body weight given intravenously
INR 4 to 6: 35 units of Factor IX/kg body weight given intravenously
INR greater than 6: 50 units of Factor IX/kg body weight given intravenously

Maximum dose:
INR 2 to less than 4: 2500 units of Factor IX
INR 4 to 6: 3500 units of Factor IX
INR greater than 6: 5000 units of Factor IX

Duration of therapy: Single dose. Repeat dosing is not supported by clinical data and is not recommended.

-Administer Vitamin K concurrently to maintain Vitamin K dependent clotting factor levels once the effects of prothrombin complex concentrate have diminished.
-Individualize dosing based on the patient's current predose International Normalized Ratio (INR) value, and body weight.
-Dose is based on body weight up to but not exceeding 100 kg. Do not exceed stated maximum dose for patients weighing more than 100 kg.
-Dosing is based on actual potency. The potency varies from vial to vial and is stated on the carton. Potency varies from 20-31 Factor IX units/mL. Nominal potency is 500 units per vial or approximately 25 units per mL after reconstitution.

What happens if I miss a dose?

Since prothrombin complex is used when needed, it is usually given as a single dose.

What happens if I overdose?

Since prothrombin complex is given by a healthcare professional in a medical setting, an overdose is unlikely to occur.

What should I avoid after receiving prothrombin complex?

Follow your doctor's instructions about any restrictions on food, beverages, or activity.

What other drugs will affect prothrombin complex?

Other drugs may affect prothrombin complex, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you start or stop using.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.