Normal values are 60-150% inhibition.

Note: Normal value ranges may vary slightly among different laboratories. Talk to your doctor about the meaning of your specific test results.

A lack (deficiency) of protein S can lead to excess clotting. These clots tend to form in veins, not arteries.

A protein S deficiency may be inherited. It can also develop due to pregnancy or certain diseases, including disseminated intravascular coagulation (DIC), liver disease, warfarin (coumadin) use, chronic antibiotic use, and HIV infection.

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Protein S Overview

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Protein S Risks

Review Date: 03/02/2009
Reviewed By: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; and Yi-Bin Chen, MD, Leukemia/Bone Marrow Transplant Program, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org)