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At a Glance
Why Get Tested?
To determine the proportion of your blood that is made up of red blood cells (RBCs) in order to screen for, help diagnose, or monitor conditions that affect RBCs; as part of a routine health examination or if your healthcare provider suspects that you have anemia or polycythemia
When to Get Tested?
With a test for hemoglobin or as part of a complete blood count (CBC) during a routine health exam or when you have signs and symptoms of anemia (weakness, fatigue) or polycythemia (dizziness, headache); at regular intervals to monitor a disorder that affects RBCs and to evaluate the effectiveness of treatment
A blood sample drawn from a vein in your arm or by a fingerstick (children and adults) or heelstick (newborns)
Test Preparation Needed?