Platelet Function Tests

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Also known as: Platelet Aggregation Studies; PFT; Platelet Function Assay; PFA
Formal name: Platelet Function Tests
Related tests: Full Blood Count; Blood Smear; Platelet Count; PT and INR; PTT; Bone Marrow Aspiration and Biopsy; Coagulation Factors; von Willebrand Factor; Clopidogrel (CYP2C19 Genotyping)

At a Glance

Why Get Tested?

To help determine the cause of, or potential for, excessive bleeding and/or to diagnose a platelet function disorder; to monitor and evaluate platelet function; to monitor the presence and effectiveness of anti-platelet medications

When to Get Tested?

When you bruise easily or experience excessive or prolonged bleeding; when you are taking medications that can alter platelet function; prior to or during certain surgeries.

Sample Required?

A blood sample taken from a vein in your arm

Test Preparation Needed?

You may be instructed to refrain from taking drugs that can affect the function of normal platelets and hence the results of these tests, such as aspirin, non-steroidal anti-inflammatory drugs (NSAIDs), or any over-the-counter medications that contain drugs such as these. The most common NSAIDs include ibuprofen, naproxen and cyclo-oxygenase-2 (COX-2) inhibitors. However, do not stop taking your medications unless instructed to do so by your health care provider.