How you prepare

If your blood sample is being tested only for a complete blood count, you can eat and drink normally before the test. If your blood sample will be used for additional tests, you may need to fast for a certain amount of time before the test. Your doctor will give you specific instructions.

Oct. 18, 2016
  1. Complete blood count. Lab Tests Online. Accessed Aug. 29, 2016.
  2. CBC with differential, blood. Mayo Medical Laboratories. Accessed Aug. 29, 2016.
  3. Understanding blood counts. Leukemia and Lymphoma Society. Accessed Aug. 29, 2016.