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A blood test is a quick and simple way to measure the amount of certain proteins, minerals, fats and sugars in your blood. By looking at the levels of these in your blood, your doctor can find out how well your body is working and whether or not you have certain conditions or health problems.
When you are first diagnosed with high blood pressure, your doctor or nurse may carry out one or more blood tests to help them plan the best treatment for you. This will show them:
- if you have a raised cholesterol level
- if you have another medical problem, such as a kidney condition or diabetes
- whether or not you have a problem with your adrenal glands or kidneys
- which medicines might work best for you.
How is a blood test carried out?
Blood tests are very common and taking blood is a simple procedure. It can usually be carried out at your local surgery by your doctor or nurse.
If your doctor or nurse only needs to know your blood sugar levels (for example when looking for diabetes), then just a small prick on the tip of a finger is needed to release a few drops of blood.
However, most tests normally require a test tube of blood, which will need to be collected by a syringe. If needles make you feel uncomfortable, speak to your doctor or nurse. They will be able to help.
Since no anaesthetics or special procedures are needed, you will be able to leave the surgery straightaway and carry on with your day as normal. If you feel faint while the blood is being taken, you may be asked to rest for a while afterwards.
Do I need to do anything before the test?
Depending on what your doctor or nurse is testing for, you might be asked to avoid eating anything for a period before the test. For example, if they want to look at your blood sugar levels, they may ask you to come in first thing in the morning, before having breakfast.
How soon will I know the results?
Your blood sample will need to be sent to a laboratory for testing, and the results will then be analysed by your doctor. This can take up to a few weeks.