From the Guidelines
You can test for protein C while on Eliquis (apixaban), but the results may not be reliable due to potential interference from the medication. Eliquis is a direct factor Xa inhibitor that can affect many coagulation-based laboratory tests, including protein C assays 1. For accurate protein C testing, it's recommended to temporarily discontinue Eliquis for at least 24-48 hours before blood collection, but this should only be done under your doctor's supervision due to increased thrombosis risk. If stopping Eliquis isn't possible, inform the laboratory that you're taking this medication so they can interpret results accordingly. Some specialized laboratories can perform chromogenic protein C assays that may be less affected by Eliquis. Key considerations for testing protein C while on Eliquis include:
- Temporarily discontinuing Eliquis for at least 24-48 hours before blood collection, under medical supervision
- Informing the laboratory about Eliquis use to ensure proper result interpretation
- Potential use of specialized chromogenic protein C assays that may be less affected by Eliquis Protein C is an important natural anticoagulant, and deficiencies can increase clotting risk, which is why accurate testing matters for proper diagnosis and treatment planning 1. Always consult with your healthcare provider before making any changes to your anticoagulation regimen.
From the Research
Testing for Protein C while on Eliquis
- Protein C is a vitamin K-dependent glycoprotein that acts as a natural anticoagulant, and its deficiency can increase the risk of thrombosis 2.
- The diagnosis of protein C deficiency can be challenging due to various preanalytical and analytical factors that may affect protein C levels 3.
- Studies have shown that protein C and protein S levels can be accurately determined within 24 hours of diagnosis of acute venous thromboembolism, and most results will be normal with false positives being uncommon 4.
- However, there is limited information on testing for protein C while on Eliquis (apixaban), a direct oral anticoagulant (DOAC).
- A study on apixaban use in patients with protein C and S deficiency found that apixaban could be effective in preventing recurrent thrombotic events in patients with inherited thrombophilia without safety concerns 5.
- Another study evaluated protein C and protein S levels during oral anticoagulant therapy and found that protein C and protein S deficient patients could be identified by ratio calculation while on warfarin therapy 6.
- It is unclear if similar methods can be used to test for protein C while on Eliquis, and further studies are needed to investigate this.