Patency capsule test (West Mid Site)

What is a patency capsule test?

A patency capsule determines whether a capsule endoscopy can safely pass through your intestine. For this procedure, you will swallow a capsule (similar size to a jelly bean) made of dissolvable material surrounding a tiny radio frequency identification (RFID) tag, which can be detected by X-ray.

If the patency capsule leaves your body before it dissolves, this confirms that your intestine does not have any major narrowing and is suitable (or ‘patent’) for capsule endoscopy.

The patency capsule test is usually a two-day visit.

Instructions

We require accurate information from this test, so please carefully follow the instructions below. From midnight on the evening before your test, do not eat or drink anything except for sips of water and/or your medication.

Day 1

• When you arrive you will meet with one of our nurses to discuss the test.
• You will be seen by the doctor who will explain the test in more detail and you can ask any questions before signing a consent form.
• You will be taken to an assessment room and asked to swallow the patency capsule with a little water.
• If you suffer from any abdominal pain, nausea or vomiting during the patency capsule test, contact the unit on 020 8321 2585 / 5191 immediately.
• After swallowing the patency capsule and until it leaves your body, avoid being near any source of powerful electromagnetic fields such as an MRI scanner.

Day 2

There will be two possible outcomes: 

• If you have seen the patency capsule pass into your poo, you can send us a good quality photo of the capsule to chelwest.endoscopy.westmid@nhs.net. Your photo will be used by our medical team to assess whether it is safe to go ahead with the capsule endoscopy.
• If you do not see the patency capsule pass, you will need to return to the Endoscopy Unit at 10am to test whether it is still inside your body. This will require an X-ray or a CT scan with a very low dose of radiation. If the patency capsule is still inside your body after 30 hours, it will dissolve into tiny pieces that can pass naturally through your intestine.

This leaflet has been written by the staff working in the Endoscopy Unit at West Middlesex University Hospital. We hope you find it useful. If, after you have read it, you have any questions or concerns; please contact us on 020 8321 5752 / 5380. If you would like to change your appointment time or date please contact the endoscopy booking team on 020 8321 6240.

How to find us

The Endoscopy Unit is located on the ground floor of the Main Hospital Building in the East Wing.

Getting here: https://www.chelwest.nhs.uk/your-visit/getting-here/west-middlesex-university-hospital