Name: Intestinal Permeability Assessment
Brand: Instalab
Price: 199.00 USD
Availability: InStock

Question 1

What is the Intestinal Permeability Test?

Accepted Answer

The intestinal permeability test is a non-invasive urine test that measures how well your gut lining functions. It works by tracking the absorption of two naturally occurring sugar molecules, mannitol and lactulose, which you drink as part of the test. By seeing how much of each passes into your urine, the test reveals whether your intestinal barrier is intact, overly permeable, or damaged.

Question 2

What does “intestinal permeability” mean?

Accepted Answer

Your intestines are lined with a single layer of cells that act as a selective barrier. This barrier allows important nutrients to pass into your bloodstream while blocking harmful substances like toxins, bacteria, and undigested food particles. Permeability describes how much gets through. A healthy barrier allows the right things in and keeps the wrong things out. If the barrier becomes too permeable, often referred to as “leaky gut,” larger molecules that should not cross begin slipping through, which may trigger inflammation, immune activation, and other health issues. If the lining is damaged, absorption can also be reduced, meaning even beneficial nutrients are not taken up efficiently.

Question 3

Who should consider the Intestinal Permeability Test?

Accepted Answer

This test is often used by people who experience ongoing digestive discomfort, unexplained bloating, diarrhea, or irritable bowel symptoms. It can also be helpful for individuals with autoimmune conditions, food sensitivities, chronic fatigue, fibromyalgia, skin conditions such as eczema or psoriasis, or unexplained inflammation. Even in people who eat a balanced diet, nutrient deficiencies sometimes persist, and barrier dysfunction can be one reason why.

Question 4

How accurate is the Intestinal Permeability Test?

Accepted Answer

The lactulose–mannitol test is one of the most widely studied and validated ways to evaluate gut barrier function. It has been used in both clinical practice and research for decades and provides measurable data rather than guesswork about how well your intestinal lining is performing.

Question 5

Do I need to fast before the Intestinal Permeability Test?

Accepted Answer

Yes. The test usually begins after an overnight fast. Your kit will include detailed instructions about preparation, including when to start and what to avoid beforehand.

Question 6

What exactly is measured in the Intestinal Permeability Test?

Accepted Answer

The test focuses on two sugars: mannitol, a small molecule that should be easily absorbed, and lactulose, a larger molecule that should mostly be blocked by a healthy barrier. Low mannitol levels suggest poor absorption, high lactulose levels indicate excessive permeability, and the ratio between the two provides the clearest overall picture of gut barrier health.

Question 7

Can I take probiotics, supplements, or medications before the Intestinal Permeability Test?

Accepted Answer

Some supplements and medications can affect permeability. Probiotics are usually fine, but antibiotics are often discouraged within a week or two of testing. Alcohol and anti-inflammatory drugs such as ibuprofen can increase gut permeability and are best avoided before the test unless otherwise directed. The safest approach is to review your supplement and medication list with your practitioner before collecting your sample.

Question 8

How is the Intestinal Permeability Test performed?

Accepted Answer

On the morning of the test, you drink a solution containing the two sugars. You then collect all of your urine over the next six hours in the provided container. Once complete, the sample is packaged and shipped back to the laboratory using prepaid materials.

Question 9

How long does it take to get results for the Intestinal Permeability Test?

Accepted Answer

Results are usually ready within two to three weeks after the laboratory receives your sample.

Question 10

What can my results show for the Intestinal Permeability Test?

Accepted Answer

The report may show normal permeability, meaning your barrier is functioning properly. It may show increased permeability, sometimes called leaky gut, which is linked to inflammation and immune reactions. It may show low absorption, which could indicate damage to the mucosal surface or villi, leading to poor nutrient uptake. Sometimes both problems are present, with leakage and poor absorption occurring together.

Question 11

Is the Intestinal Permeability Test the same as colon cancer screening?

Accepted Answer

No. This test does not detect cancer. Colon cancer screening is performed with imaging or stool-based tests that look for blood or genetic mutations. The intestinal permeability test is focused specifically on barrier function and nutrient absorption.

Question 12

How does the Intestinal Permeability Test compare to a stool test?

Accepted Answer

A stool test analyzes the microbes living in your gut and markers of inflammation. The intestinal permeability test looks at how well the gut lining itself is functioning. They provide different but complementary information—one describes the ecosystem of your microbiome, while the other describes the strength and performance of the barrier that separates your gut contents from the rest of your body.

Question 13

How often should I repeat the Intestinal Permeability Test?

Accepted Answer

Many people repeat the test after three to six months of gut-healing treatment to track progress and confirm improvement. Retesting can be especially helpful when making significant dietary or lifestyle changes, or when monitoring recovery from a gut disorder.

Question 14

Where is my sample processed for the Intestinal Permeability Test?

Accepted Answer

All samples are analyzed at Genova Diagnostics, a CLIA-certified laboratory that specializes in advanced functional medicine testing.

Question 15

Will my insurance cover the Intestinal Permeability Test?

Accepted Answer

Instalab does not accept insurance at this time. However, you may be eligible for reimbursement if you have an HSA/FSA. We recommend using your HSA/FSA card for purchases. An itemized receipt can be generated for reimbursement purposes if needed.

Question 16

Can the Intestinal Permeability Test detect food sensitivities?

Accepted Answer

Not directly. The test does not measure immune reactions to specific foods. However, increased intestinal permeability is strongly associated with the development of food sensitivities, because larger food antigens can cross the barrier and trigger an immune response.

Question 17

What if I’m menstruating during collection for the Intestinal Permeability Test?

Accepted Answer

It is best not to perform the test during menstruation, since blood in the urine could interfere with the results. If your cycle coincides with your planned collection, consider postponing.

Question 18

What if I miss part of the urine collection period for the Intestinal Permeability Test?

Accepted Answer

The accuracy of the test depends on complete urine collection over the six-hour window. If part of the collection is missed, the results may not be reliable, and your practitioner may suggest repeating the test.

Question 19

How should I store my sample before sending it for the Intestinal Permeability Test?

Accepted Answer

You will be given clear instructions with your kit. Most samples need to be refrigerated until they are shipped. Prepaid FedEx materials are provided to make shipping straightforward.

Question 20

Does the Intestinal Permeability Test check for SIBO (Small Intestinal Bacterial Overgrowth)?

Accepted Answer

No. SIBO is usually diagnosed with a breath test, not a permeability test. However, bacterial overgrowth can contribute to barrier dysfunction, so your practitioner may recommend both tests if symptoms suggest overlap.

Find out if leaky gut is contributing to your symptoms

How it works

This test is designed for people who

What's included in your report

Frequently asked questions

Find out if leaky gut is contributing to your symptoms

How it works

This test is designed for people who

What's included in your report

Frequently asked questions