How To Prepare For Your Lab Tests


It’s important to tick all of the boxes when preparing your lab tests to ensure that you get the most accurate results possible. Your preparation as a patient is the most important factor in determining how well the lab can process and accurately identify your samples. Whether you’re sending in blood, stool, hair, etc. samples, the crucial thing to remember is how you prepare for your lab tests can affect the results of those tests! So, make sure you follow the instructions closely, so you get the right answers from your lab tests and not skewed ones.  

How To Prepare For Your Lab Tests

There are three essential things to keep in mind prior providing and/or collecting your sample for testing. These apply to whether you are going to a lab or using an at home kit.

Follow All Instructions

Not all tests have the same requirements. Some require fasting. Others don’t. All of the tests, however, come with instructions. Do not wing it.

Fess Up

Things happen. Sometimes, even with the best of intentions, something goes awry in the pre-test process. Don’t pretend it didn’t. Tell the person collecting the sample how you deviated. That deviation may skew the results, which provides false information. No one wants that!

Be Thorough

Tell your healthcare practitioner of any medications you are on. This includes if you’re taking vitamins or supplements. Be as specific as possible. What time did you take your last dose of each medication? This is the sort of information needed by your healthcare provider to could help shape the course of action after receiving the results of the test.

That being said, many tests don’t even require prior special preparation. On the off chance you don’t receive instructions, don’t assume that there aren’t any. Ask either your doctor or us for clarification.

Some of what you might be asked to refrain from doing prior to testing might not seem intuitive. Certain behaviors may affect the results of some tests: recent or excessive exercise, dehydration, excessive eating and even sex. There is the possibility you might be asked to refrain from these activities prior to testing. Or in the case of dehydration, making sure properly hydrated.

By far the most common thing requested prior to testing is fasting. The length of fasting can vary, so make proper note of that should it be required. It might not even be fasting of all food and drink, but just specific items. For example, herbal tea may throw off the results of some blood panels.

Here’s a list of common lab tests that DO require advance preparation:

Glucose Test – Fasting or eating meals at specific times may be required. If you’re already diabetic, glucose levels may be checked prior to eating and after eating for comparative results.

Lipid Panels – These panels test triglycerides and cholesterol for example. Fasting for 9-12 hours may be required.

Creatinine Test – This requires overnight fasting, especially of eating cooked meat. Some studies show that cooked meats prior to testing can temporarily increase the level of creatinine in the body.

Fecal Blood Test – This is a test to determine if there’s bleeding the in the digestive tract, so certain foods and/or medications may need to be restricted during the testing period.

Urine Test –  A patient might be instructed to not go to the bathroom one hour prior to testing. Also, it’s possible that the patient may be asked to drink a glass a water 15-20 minutes before sample collection.

5-HIAA Test – Specific foods might be forbidden for 3 days before and during the collection of a urine sample. These foods are avocados, bananas, pineapples, plums, walnuts, tomatoes, kiwi fruit and eggplant. Also, certain medications might need to be stopped as all of these can affect test results.

Cortisol Test – It may be necessary to rest before giving a sample. And in the case of a saliva sample, you may be asked to refrain from eating, drinking or even brushing your teeth!

Walk-in Lab tests have preparation requirements at the top of each test in a block of text called Additional Information. On our website, this can be found right under the Add To Cart button. Again, if you have any questions in regards to test preparation, please ask. It’s much easier to deal with before the test than after.