Blood tests are one of the most common ways your health care team can get an overall picture of your health. Most adults should have a series of blood tests done every year as part of an annual physical exam. 

A blood test can measure:

• Hormones
• Protein 
• Electrolytes
• Minerals
• Red and white blood cell counts
• Cholesterol

Why Would I Need a Blood Test?

There are many reasons why your primary care provider (PCP) might order a blood test for you. The top five most common blood tests measure everything from platelets and blood cell count to enzymes and proteins and your blood glucose level.

A blood test may be needed because:

• It’s part of your routine exam, and your PCP would like to know more about your blood, including a complete blood count (CBC), a basic metabolic panel (BMP) or a comprehensive metabolic panel (CMP). 
• You need a screening test to see if you are at risk for certain diseases or conditions, such as kidney disease or liver disease.
• Blood testing can show if certain treatments you are receiving are working: cancer treatment, for example.
• You have a condition, such as diabetes, and need to check a part of your blood’s makeup such as blood glucose.
• You need to be checked for vitamin deficiencies such as low vitamin D. 

When Should I Have a Blood Test?

The best time is during your annual wellness visit, or any time your PCP suggests you should have bloodwork done. For example, if you are feeling unusually run down and don’t know why, they may have a blood lab test done to check hormone, glucose and red blood cell levels.

What Kinds of Blood Tests Are There?

The most common kinds of blood sample tests are:

• CBC counts and measures parts of your blood such as red blood cells, white blood cells, hemoglobin, platelets and hematocrit (the percentage of red blood cells in your blood).
• BMP measures blood glucose, calcium, blood urea nitrogen (BUN), creatine kinase and many other substances in your blood. High levels of blood glucose (sugar in the blood) can indicate conditions such as prediabetes. 
• CMP tests everything in the BMP, but also gives information on your fluid balance, liver function, kidney function, electrolytes and sodium.
• Lipid panel testing shows the amount of fat molecules (called lipids) in your blood. This includes cholesterol.
• Hormone panel test includes thyroid levels.

How Long Does It Take?

A blood test is done in your health care provider’s office or at a clinic, including many locations in Louisville and the surrounding areas. It should only take a few minutes. Test results are available in your Norton MyChart account as soon as the lab completes testing. Your PCP typically reviews results in two to three business days. If there is anything concerning, your doctor will call you and possibly schedule a follow-up appointment. Remember, reading your results on Norton MyChart is not a substitute for careful medical guidance from your health care provider. 

Some tests, such as a blood glucose test, require you to have fasted for 12 hours before blood is drawn. That means no food or drinks besides water until the blood is taken. You can see a primary care provider or you can use a convenient drive-thru location. You can compare your test results from previous years via Norton MyChart. Talk to your health care provider about whether blood testing is right for you and which tests you might need.