Blood Test

What is a Blood Test? It’s Purpose, Procedure, and Results.

You must have gone through a blood test at least once in a lifetime. It is a first-line test. If a doctor wants to know about any abnormality in the body, they first prescribe this test. From fever to cancer, every diagnosis starts with a test involving an extraction of your blood sample. Yes, it is an integral part of the healthcare sector.

It is used for analyzing full-body health. Along with catching any pathogen, a test may tell the overall health of your body, starting from RBC count, WBC count, Haemoglobin, and more. Let us see what a Blood plasma test is and why it is done.

What is a Blood Test?

Doctors generally prescribe a Blood Test or Blood panel test for certain health issues and diseases. It is a standard medical test used for determining abnormality in your body. It can even be a part of routine body checkups or for detecting certain diseases.

Types of Blood Tests

However, different kinds of tests are performed for various health aspects. Some focus on your blood cells and platelets, whereas some evaluate substances in your blood, such as electrolytes, proteins, and hormones.

No single test can determine all health issues related to your body. Specific tests are required to detect specific conditions. These tests are prescribed as per the symptoms. 

Here are the common types of blood tests:-

  • Complete blood count (CBC): The CBC test shows the counts of white blood cells, red blood cells, and platelets, the concentration of hemoglobin, and the hematocrit. 
  • Basic metabolic panel (BMP): A BMP is a test of seven or eight biochemical tests. 
  • Comprehensive metabolic panel (CMP): CMP is a test to determine the body’s metabolism and chemical balance.
  • Lipid panel: A lipid profile is done to know certain genetic diseases and risks for cardiovascular disease, certain forms of pancreatitis, and other conditions.
  • Thyroid panel: TFTs is done if a person is suffering from the symptoms of hyperthyroidism or hypothyroidism. 
  • Cardiac biomarkers: Cardiac biomarkers are a kind of test used to determine heart functions.
  • Sexually transmitted infection tests: STI test is done to determine whether you are suffering from sexually transmitted infections. 
  • Coagulation panel: A coagulogram is done to diagnose the hemostasis system.
  • Electrolyte panel: An electrolyte panel, or serum electrolyte test, measures levels of the body’s main electrolytes.
  • BNP Test: The BNP test is to determine heart functioning. It measures the levels of a protein called BNP in your bloodstream.
  • ANA Test: An ANA test is done to see antinuclear antibodies in the blood. 
  • MCH Test: The MCH test measures the amount of hemoglobin in a single red blood cell. 
  • MCV Test: It measures the average size of red blood cells.
  • INR Test: INR test indicates how long it takes for your blood to clot.

Specialized Blood Tests

  • Ammonia levels: It may be done to see the amount of ammonia in your blood. High levels usually indicate a health issue or may be a sign of liver and kidney damage.
  • Blood alcohol content (BAC): The blood alcohol content test, or BAC, shows the amount of alcohol in our body.
  • Ferritin: A ferritin test may be conducted if your CBC indicates lower iron levels in your system. 

When to Undergo a Blood Test?

Your blood plays an important role in your overall body health. If you feel unwell or experience any symptoms, you should get a blood test. Given below are the conditions when you should have a blood test done:-

  • Regular Physical Examination: Your doctor prescribes a blood test as part of your physical examination. Generally, a complete blood count (CBC), basic metabolic panel (BMP), or comprehensive metabolic panel is done.
  • Screening Test: Your provider recommends having a screening test before you develop symptoms of the disease, such as cancer. 
  • You don’t feel well: If you do not feel well internally, your doctor may prescribe having a blood test to determine the cause. 
  • Mutation-related health issues: Your doctor may suggest undergoing the test if you are experiencing mutation-related health issues due to genes or environmental factors. 
  • On-going treatment: Blood tests may be part of your therapy if you are receiving treatment for a particular disease. 

What Does A Blood Test Show?

In a nutshell, blood tests show the overall health condition of your body. Whatever changes your body goes through it will be visible in the test. 

Given that, here is what doctors generally see in a blood test:-

  • Working of the blood: A test will indicate the normal or abnormal functioning of blood. The work of blood is to bring oxygen and transfer material. If this function is disrupted, you may face health issues. 
  • Any unwanted pathogen: It may be done to see if there is any unwanted pathogen in your bloodstream. Certain conditions, such as AIDS, are a result of Adenovirus entering the blood.
  • Levels of enzymes and electrolytes: Enzymes are crucial to speeding up the chemical reactions that build up and break down substances in your body. On the other hand, Electrolytes help regulate chemical reactions and maintain a balance between fluids inside and outside your cells.

How is a Blood Test done?

Your blood must be tested by a healthcare professional. Generally, it takes about 10 minutes to collect the blood. The procedure involves taking a small amount of blood; usually, 30 ml of blood is taken in the CBC test. 

To do this, your technician will:-

  • Wear sanitary gloves
  • Secure the patient’s arm with a rubber band
  • Clean the area with an antiseptic
  • Insert the needle
  • Draw enough blood
  • Remove the needle
  • Apply an adhesive bandage

After this, the blood sample is transferred to a special vial that contains chemicals to prevent clotting. Then, the sample is sent to the laboratory for analysis. As soon as the sample is sent to the laboratory, your blood will be put to the test. Reports will be generated within 12 to 24 hours, and you will be called by your healthcare provider for collection. You may discuss the reports with the doctor, depending on your reports.


A blood test is a standard health test that helps determine the body’s overall condition. If your test reports are regular, you may be safe from most diseases. However, the condition is not always true, and there may be opposite scenarios. That is why you should contact a healthcare provider for the exact diagnosis and treatment if you are facing any symptoms. 

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Arushi Chaturvedi

I'm an enthusiastic content writer who makes information interesting and easy to understand. I can write any topic from sports to technology and make it fun to read. Also good at using internet to make sure people can find my writing easily. If you reach here and still reading, I am your person.