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  2. Taking a test
  3. Intestinal Permeability (Leaky Gut) Test

How do I take the Leaky Gut (intestinal permeability) Test?

Understand how to prepare and take the sample for this test.

Preparing for your test 

  • You must fast for at least 3 hours before taking the test. For this reason, most people find it easiest to take this test first thing on waking.
  • You must not eat or drink anything (apart from the PEG dose) during the first 2 hours of test. 
  • You must return the sample within 72 hours. If there’s any delay in posting, it’s important that you put the sample in fridge.
  • If you have any questions or issues with taking your sample according to the instructions provided, it is important you contact us before you send your sample to the labHealthpath cannot guarantee to intercept your sample once it arrives at the lab, so it may still be processed.

Do NOT take the test if:

  • You have diarrhoea or gastroenteritis.
  • You’re taking medication containing Movicol (Macrogol).
  • You’re taking a diuretic.
  • You’re taking the supplements Zinc or Vitamin C (stop 3 days before the test)
You must wait until digestion is normal before taking this test.

You must NOT stop taking any medication in order to take the test.


Test kit contents

  • 1 x test instructions sheet 
  • 1 x patient request form
  • 1 x 3g PEG dose
  • 1 x antibacterial wipe
  • 1 x empty sample bottle
  • 1 x plastic transport tube
  • 1 x pair of gloves
  • 1 x return envelope
  • 1 x freepost address label
  • 1 x biological substance label 

Taking the test 

Check you have all the test kit contents using the list above, and fill in the request form

clock-01 2. After fasting for at least 3 hours, empty your bladder (a.k.a. do a wee)
solution-01-1 3. Mix the PEG dose with 250ml water and drink immediately.
Collect all urine passed during the next 6 hours into a convenient washed container. A container with a capacity of 1.5 litres (such as a washed water bottle, no soap ) works well.

Do not eat or drink anything for 2 hours after drinking the PEG dose. Make sure the last urine collection is exactly 6 hours after taking the PEG dose.

take-sample-01 6. If you can accurately measure the total volume of urine collected, you can return a small well-mixed sample in the empty sample bottle provided. Make sure you label the sample bottle with your name, PEG TEST, date of birth and the total volume of urine collected.

(This is important, as it's require for accurate interpretation of your results).
If you can't work out the total volume of urine collected, you can return the full sample. Clearly label the urine container with your name and date of birth and 'PEG TEST'.

dispose-01 8. Place the sample in the plastic transport tube, ready for posting.


Posting your sample 

  1. Return your sample along with the completed patient request form and return to the laboratory within 72 hours. If there's any delay in posting, make sure you put the sample in the fridge.
  2. Attach your Biological Subtance Category B label and Freepost Healthpath label to the return envelope. The label only says 'Freepost HEALTHPATH' but rest assured, that's the only information the Post Office needs. Read about using Freepost for Healthpath tests.
  3. If you would prefer to arrange a recorded delivery, the address is Biolab Ltd, The Light Box, 111 Power Road, London W4 5PY.

What happens next?

Results take 10-15 working days from receipt of sample.

As soon as your results are ready, we'll send you an email and text to let you know.

You can then log onto your Healthpath account to view your results and see personalised recommendations.