Individual test · Labcorp 164525

Protein S, Functional

This test measures the activity of Protein S, a substance in your blood that helps stop clots from growing too large. It helps doctors investigate the cause of unexplained blood clots or a family history of clotting disorders. The results help show whether a deficiency in this protein is contributing to an increased risk for dangerous clots in your veins. However, this test does not diagnose the specific genetic cause of a deficiency on its own, and results can be affected by certain medications or other blood conditions.