Complete Blood Count (CBC)
What Affects the Test
Reasons you may not be able to have the test or why the results may not be helpful include:
- If the elastic band was on your arm a long time while the blood sample was taken.
- Taking medicines that can cause low platelet levels. Some examples of the many medicines that cause low platelet levels include steroids, some Reference antibiotics Opens New Window, thiazide diuretics, chemotherapy medicines, quinidine, and meprobamate.
- A very high white blood cell count or high levels of a type of fat (Reference triglycerides Opens New Window). These can cause falsely high hemoglobin values.
- Having an enlarged Reference spleen Opens New Window Reference Opens New Window, which may cause a low platelet count (Reference thrombocytopenia Opens New Window) or a low white blood cell count. An enlarged spleen may be caused by certain types of cancer.
- Pregnancy, which normally causes a low RBC value and less often a high WBC value.
|By:||Reference Healthwise Staff||Last Revised: Reference August 6, 2012|
|Medical Review:||Reference E. Gregory Thompson, MD - Internal Medicine
Reference Joseph O'Donnell, MD - Hematology, Oncology