What not to do before lab work?

Other common test preparations include:
  • Avoiding specific foods and drinks such as cooked meats, herbal tea, or alcohol.
  • Making sure not to overeat the day before a test.
  • Not smoking.
  • Avoiding specific behaviors such as strenuous exercise or sexual activity.
  • Avoiding certain medicines and/or supplements.


What should you not do before a blood test?

Recommendations for how to prepare for blood test:
  • Avoid drinking or eating anything for 8-12 hours before the test. ...
  • You should not eat 3 hours before the clinical blood test.
  • Eat less fatty and fried food, and avoid alcohol 1-2 days prior to the test.
  • Don't smoke 1 hour prior to the test.


What is the best thing to do before blood work?

Here's how to make the blood draw easier
  • Get a good night's sleep and drink plenty of water. ...
  • Ask your doctor if you need to fast before the blood draw. ...
  • Wear short sleeves. ...
  • Take your prescribed medications beforehand unless a health care professional advises you otherwise.
  • Bring your insurance card and identification.


What can affect the results of a blood test?

Lots of things can affect certain lab test results, like:
  • Fasting vs nonfasting.
  • Being well hydrated vs dehydrated.
  • Medications.
  • Intense physical activity.
  • Some foods (like avocados, walnuts, and licorice)
  • Sunburn.
  • Colds or infections.
  • Having sex.


What should you avoid the night before blood work?

If your appointment is at 8 a.m. and you're told to fast for 8 hours, only water is OK after midnight. If it's a 12-hour fast, avoid food and drink after 8 p.m. the night before. You also shouldn't smoke, chew gum (even sugarless), or exercise. These things can rev up your digestion, and that can affect your results.


Vital Minute: The do’s and don’ts of fasting before routine bloodwork



What can throw off a cholesterol test?

Drugs such as birth control pills, hormone replacement therapy, steroids, and blood pressure medication such as beta-blockers and diuretics can raise cholesterol levels and affect cholesterol test results.

Should I drink a lot of water the night before a blood test?

Ideally, start drinking more fluids the day before your blood draw, and continue to drink water before you have your blood drawn. Excessive amounts aren't necessary; most sources ecommend that an adult drink 64 ounces of water per day for good health, which is more than adequate for having your blood drawn.

What medications affect lab tests?

Common drugs that can interfere with lab tests
  • Antibacterials. Antibacterial agents are the drugs most likely to interfere with laboratory tests, with cephalosporins at the forefront. ...
  • Psychotropics. ...
  • Contrast media. ...
  • Proton pump inhibitors. ...
  • Biotin. ...
  • Acetaminophen. ...
  • Amiodarone. ...
  • Chloroquine and quinine.


Can stress affect blood work results?

Physiological studies have shown that stress can affect the blood cell parameters1. These changes include increase in red blood cells, platelets and neutrophil count whereas eosinophils, lymphocytes and monocytes are said to decrease in number.

Does what you eat the day before affect a fasting blood test?

McKnight also mentioned the food or drinks you consume the day or night before a blood test does not impact your test results, unlike what you eat or drink the morning of your test. “It's recommended that you avoid coffee and other liquids during your fast,” McKnight said.

How much water should I drink before a blood test?

This is generally the case for blood tests and surgeries. If your phlebotomy specialist says it is OK to drink water before getting blood drawn, try to drink the recommended daily amount of water, which is 64 ounces. Before you donate, drink a glass of water that's about 16 ounces.


Can I brush my teeth before blood test?

​Yes, brushing your teeth is permitted unless otherwise indicated by your physician, assuming you do not use large amounts of toothpaste and swallow the lather.

What should you do the morning before a blood test?

You can eat and drink as normal before some blood tests. But if you're having a "fasting blood test", you will be told not to eat or drink anything (other than water) beforehand. You may also be told not to smoke before your test.

How can I improve my blood test results?

For Accurate Blood Test Results: Fast

Nutrients and ingredients in the food and beverages you eat and drink are absorbed into your bloodstream. This could impact factors measured by certain tests. Fasting improves the accuracy of those tests, Dr. Krajcik says.


Will coffee affect blood work?

Even if you drink it black, coffee can interfere with blood test results. That's because it contains caffeine and soluble plant matter, which might skew your test results. Coffee is also a diuretic, which means that it will increase how much you pee. This can have a dehydrating effect.

Can bloodwork tell if you have anxiety?

Anxiety is not a simple diagnosis. It's not caused by a germ that can be detected in a blood test. It takes many forms and can also accompany other medical conditions. To diagnose anxiety, a complete physical examination is essential.

How can I calm my anxiety for a blood test?

Distraction is your best friend
  1. Watch a video or listen to music on your phone and close your eyes.
  2. Bring a friend who'll keep you engaged in conversation.
  3. Visualise being somewhere else. Close your eyes and take yourself to the beach or somewhere relaxing.


Can a blood test tell if you have anxiety?

To diagnose an anxiety disorder, a doctor performs a physical exam, asks about your symptoms, and recommends a blood test, which helps the doctor determine if another condition, such as hypothyroidism, may be causing your symptoms. The doctor may also ask about any medications you are taking.

Can I take my prescription pills before a blood test?

Most of the time, it's advised to take regular medications before a fasting blood test. Often, it's advised to continue taking your regular medications, even before a fasting blood test. But, its always good to clear this with your doctor, as well as any vitamin or supplements that you take on a daily basis.

Can I take my meds before labs?

Most of the time it's OK to take your usual medicines, but you may need to avoid certain medicines, especially if they need to be taken with food.


Should you stop vitamins before blood test?

You should always tell your doctor about any vitamins or herbal products you are taking and ask about the possible effects. A few labs told me that in most cases and depending on the dose, you could skip your vitamin or supplement for a day to a week before your test to prevent any issues.

What not to do after getting blood drawn?

Recommendations After Blood Collection
  1. Avoid tight or restrictive clothing on the arm.
  2. If bleeding occurs, apply firm pressure with your fingers directly over the needle site.
  3. Avoid strenuous use of the arm eg sports or heavy lifting.


Is 7 hours of fasting enough for blood test?

How long should you fast before a blood test? The amount of time you need to fast for will vary depending on the test. For most tests, you will be told not to consume anything but water for eight hours leading up to the test. For a few tests, a 12-hour fast may be needed.


What blood tests require 12 hour fasting?

This blood test assesses the amount of cholesterol and triglycerides in our blood. Fasting time: 12 hours.
...
Here are the blood tests that require fasting:
  • Blood Glucose Test. ...
  • Gamma Glutamyl Transferase (GGT). ...
  • Glucose Tolerance Test. ...
  • Liver Function Test. ...
  • Renal Function Test. ...
  • Vitamin B12 Test.


How can I lower my cholesterol the day before a test?

Foods to lower cholesterol
  1. barley.
  2. oats.
  3. okra.
  4. eggplant.
  5. nuts, such as almonds, peanuts, and walnuts.
  6. beans, such as kidney beans, garbanzo beans, and black-eyed peas.
  7. lentils.
  8. fruits, such as apples, citrus fruits, and strawberries.