A blood test is a routine medical test that helps doctors diagnose and manage a wide range of medical conditions. It involves taking a small sample of blood from your body and analysing it in a laboratory. This analysis can reveal a lot of information about your health, such as your blood sugar level, cholesterol level, liver function, and kidney function. Here are some essential things you must know before a blood test.
1. Fasting
Fasting means avoiding food and drink for a specified period before the blood test. Some blood tests require fasting, while others do not. Doctors or pathologists request patients to fasting for eight to twelve hours before a blood test, especially for the one that measure blood glucose (sugar) and lipids (cholesterol and triglycerides). Fasting helps to ensure that the test results are accurate. And helps ensure the levels of glucose and lipids in your blood are not influenced by recent food intake. Therefore, it’s important to follow the fasting instructions given by your doctor or laboratory experts.
2. Medications
Some medications can affect the results of blood tests. So, it is essential to tell your doctor about all the medications you are taking, including prescription drugs, over-the-counter medications, and dietary supplements. Some medications may need to be stopped before the blood test, while others can be taken as usual. Your doctor will advise you on which medications to stop and when to stop them. You should not stop taking any medications without consulting your doctor.
3. Physical Activity
Strenuous physical activity can affect some blood test results, such as creatine kinase (CK) and lactate dehydrogenase (LDH), which are markers of muscle damage. Therefore, it is important for you to avoid strenuous physical activity for 24 hours before the blood test. However, light to moderate physical activity, such as walking or yoga, is generally okay.
4. Hydration
Drinking enough water is essential for accurate blood test results. Dehydration can cause changes in some blood test parameters, such as electrolytes and kidney function tests. Therefore, it is essential to drink enough water before the blood test. However, overhydration can also affect some blood tests, such as those that measure electrolytes and blood volume. Therefore, it’s important to follow your doctor’s instructions regarding hydration before the blood test.
5. Timing
Some blood tests are affected by the time of day. For example, cortisol, a hormone that is measured in some blood tests, follows a circadian rhythm and is highest in the morning. Therefore, if you are having a cortisol blood test, it is best to do it in the morning. Similarly, some blood tests may require multiple samples taken at specific intervals, such as glucose tolerance tests. Therefore, it’s important to follow the timing instructions given by your doctor or laboratory.
6. Blood Draw Procedure
The blood draw procedure itself is usually quick and simple. However, it can be uncomfortable for some people. The healthcare provider will clean the skin over the vein with an antiseptic solution and use a needle to draw the blood into a collection tube. You may feel a prick or sting when the needle is inserted, but the procedure should not be painful. If you are anxious or afraid of needles, let your healthcare provider know, as they may be able to offer you strategies to help you relax.
7. After the Test
After the blood test, it is important for you to follow any instructions given by your doctor or pathologist. Some people may experience bruising, swelling, or mild pain at the site where the blood was drawn. Applying pressure to the site for a few minutes can help to reduce these symptoms. It’s also important to stay hydrated after the blood test and to avoid strenuous physical activity for a few hours.
In summary, a blood test is an essential diagnostic tool that can provide valuable information about your health. Having an idea about the essentials will help you prepare yourself for a blood test. And you can ensure that you get the most accurate and valuable results possible.