A complete blood count, or CBC, is a blood test that evaluates your overall health. It can pick up on early signs of many possible disorders.

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What is a complete blood count?

Your healthcare provider might order a complete blood count to get a sense of your overall health. This test measures several components of your blood, including:

  • White blood cells, which fight infections
  • Red blood cells, which carry oxygen to all the parts of your body
  • Hematocrit, the ratio of red blood cells to your total volume of blood
  • Hemoglobin, the protein in red blood cells that carries oxygen
  • Platelets, tiny cells that help with clotting

When one of these factors is out of the normal range, it can be a signal that something is wrong. Your healthcare provider may call for more tests.

Why is a complete blood count important?

If you are experiencing certain symptoms, like fatigue, fever, bruising, bleeding, inflammation or weakness, your healthcare provider will want to test for certain conditions. A complete blood count can provide information to help rule out various health problems.

For example, the test can be used to rule out or confirm anemia. If you don’t have enough red blood cells or hemoglobin, you may have anemia. Anemia makes you feel tired and listless.

However, your healthcare provider might also order other tests if your results are not in the normal range. A CBC by itself is not enough to diagnose other conditions. For example, if your test results show a low white blood cell count, you may have an autoimmune disorder. But you could just have an infection. More tests are needed in those cases.

What should you expect with a complete blood count?

A CBC test is a simple blood test. The lab technician will draw blood from a vein in your arm. The blood will then be tested in the lab. You can eat and drink normally before the test.

If you have been feeling tired or weak, seek a healthcare provider for a prescription or further testing. Visit your nearest CareNow® urgent care clinic for diagnosis and treatment. You can minimize your wait time with our Web Check-In®.

Our CareNow® urgent care clinics are open seven days a week and welcome walk-in patients. Or, try our Web Check-In® feature to avoid wait times from the comfort of your home.

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