Factor Levels and Inhibitor Panels

Also known as: coagulation factor tests, blood inhibitor panels.

What are factor levels and inhibitor panels?

Factors or coagulation factors are blood proteins that help blood clot. There are different types of coagulation factors. Factor levels are common blood tests done to determine which protein is deficient and the severity of the deficiency. Inhibitors may occur in individuals with Hemophilia. Inhibitors are antibodies.

What happens during the test?

Factor levels and inhibitor panels are obtained through a blood draw. The blood is then analyzed in a laboratory and resulted.

Is any special preparation needed?

In most cases, no special preparation is needed for these lab tests.

What are the risk factors?

Bleeding at the site of the blood draw is the most common risk factor. Less likely an infection will occur at the site.

Reviewed by: Guillermo R De Angulo, MD

This page was last updated on: September 16, 2025 12:45 PM

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Hemophilia B

Hemophilia is a disease in which the blood is missing a component that makes it clot properly. The result is that the individual with hemophilia can bleed easily, bleed excessively or not stop bleeding once they start, among other problems. In the case of hemophilia B, the blood is deficient in factor IX.

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Hemophilia is a disease in which the blood is missing a component that makes it clot properly. The result is that the individual with hemophilia can bleed easily, bleed excessively or not stop bleeding once they start.

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