How to prepare for a fasting blood test

Read this tip to make your life smarter, better, faster and wiser. LifeTips is the place to go when you need to know about Blood Tests and other Health Screenings topics.

How do I prepare for a fasting blood test?

How to prepare for a fasting blood test

Some chemicals in the human body respond to food and drinks; consuming these foods or beverages changes the levels of these chemicals in your body. Your doctor may request a fasting blood test so she can measure baseline levels, unaffected by food.

Ask your doctor if you can take your regular medications while you are fasting.

Schedule the laboratory appointment for the morning, if possible. Let the receptionist know if you will be taking any medications during your fast or if you have an illness or medical condition that prevents you from fasting.

Ask the receptionist how long you should fast – it is usually 8 to 12 hours. Ask her to help you determine what time you should start your fast, if necessary. Ask the receptionist if you can drink water during your fast – it is usually allowed.

Eat a nutritious dinner at the usual time. Take all medications as directed by your doctor.

When your fast begins, do not eat or drink anything except for water, if it is allowed. Smoking is not usually allowed.

On the day of your appointment, bring something to eat and drink. Hunger may make you lightheaded after having your blood drawn.

When you arrive for your appointment, tell the receptionist the last time you had anything other than water to eat or drink. If you were unable to maintain your fast, ask if you should reschedule or if she could make a note on your results.



Nobody has commented on this tip yet. Be the first.


URL: (optional)


Not finding the advice and tips you need on this Health Screenings Tip Site? Request a Tip Now!

Guru Spotlight
Kristle Jones