Preparation and Procedure
Preparation will depend on the reason this test is being performed. While fasting is not always required, patients may have to refrain from eating or drinking for nine to 12 hours prior to the test. Water may be permitted, however, if the doctor says the patient can have it.
In most cases, the patient can continue taking his or her medications, though, some medications may need to be stopped or adjusted before the test per doctor's orders.
Before having this test, usually for at least one to two days prior, patients must not consume alcohol or high-fat foods.
This is a simple blood test in which a blood sample is obtained via using a needle and inserting it into a vein. The technician will allow enough blood to collect, will remove the needle, and the test is complete.
Most patients do perfectly fine for this test, but a small percentage have reported feeling pain during and after they have their blood drawn.