No, the ICT serum test does not cause discomfort. It is a simple blood test that involves inserting a needle into a vein in the arm to draw blood. Nevertheless, as with any blood test, there is a minor risk of bleeding, infection, or bruising at the place where the needle is inserted. Individuals using blood thinners or having a bleeding problem may be at a higher risk of bleeding and should notify their healthcare practitioner before the test.