Oesophageal physiology studies

This leaflet has been written by staff working in the Endoscopy Unit at Chelsea and Westminster Hospital.

We hope you find it useful. If, after you have read it, you have any questions or concerns, please ring us on our direct line 020 3315 3056/5223.

When you come into the Unit (2nd Floor, Lift Bank B), please talk to us about any worries and ask any questions you have.

If you would like to change your appointment time or date, please contact the Endoscopy Unit booking team on 0203 315 4141/5984 or email us Chelwest.cwdiagnosticcentre.admin@nhs.net.

Your appointment time in Endoscopy is approximate because some procedures may take longer than expected and emergency procedures need to take priority. Please expect to be in the department for several hours – having pre-procedure checks, the procedure and for recovery after the procedure.

What are oesophageal physiology studies?

There are two parts to oesophageal physiology studies:

Oesophageal manometry measures the pressure within the oesophagus and how well the muscles are coordinated when you swallow. From this we can make an assessment of its function and determine if your symptoms are due to certain disorders of the oesophagus.

Oesophageal pH studies measure the amount of acid in your gullet and measure the degree of acid reflux.

These tests are performed to assess certain problems such as heartburn, reflux, chest and abdominal pain and problems with swallowing. Both tests are required before anti-reflux surgery can be considered.

What should I do before I come in?


Before the test you should stop taking all of the following medicines, as they will interfere with pH recording:

MedicineWhen to stop
  • Omeprazole (losec)
  • Lansoprazole (Zoton)
  • Pantoprazole (Somac, Tecta, Pantoloc, Protium, Protonix)
  • Esomeprazole (Nexium)
  • Rabeprazole (Aciphex, Pariet)
1 week (7 days) before the test
  • Ranitidine (Zantac)
  • Cimetidine (Tagamet)
  • Famotidine
  • Nizatidine
  • Metoclopromide
  • Domperidone
  • Cisapride
48 hours (2 days) before the test
  • Gaviscon
  • Sucralfate
  • Milk of Magnesia
  • Any other antacids bought from the chemist
24 hours (1 day) before the test



It is best to perform this test on patients with an empty stomach. Therefore we advise that you only have sips of water for 4 hours prior to the test.

What are the benefits and risks?

The benefit is that this procedure will help us to investigate your symptoms and it may help us treat you.

There are no serious risks. There is a small risk of the procedure causing a nose bleed, and you may have a sore throat for 24–48 hours afterwards.

What will happen when I come in?

When you arrive, the doctor or physiologist will ask several questions about your health and current medication.

The doctor or physiologist will also ask for your permission (consent) to do the procedure.

If there is anything you do not understand, or you need more time to think, please tell the doctor

What will happen during the procedure?

The doctor will perform the procedure in a private room. There are two parts to the test.

Part 1: Approximately 20 minutes’ duration

You may receive a local anaesthetic spray into one of your nostrils as well as the back of your throat, which will taste unpleasant but will not be painful.

A thin flexible plastic tube will be passed through your nose, over the back of your throat and into your stomach.

You will be asked to drink a small amount of water through a straw to help the tube go down.

This part of the procedure is sometimes a little bit uncomfortable and can make you cough or gag, but this should only last a minute or so.

Once the tube is in position, you will be asked to lie down and the doctor will slowly withdraw the tube while the computer records measurements. 

A syringe will be used to squirt a small amount of water into your mouth which you will then be asked to swallow. This will be repeated 10 times. Additional swallow assessments (e.g. by eating biscuits) may be required.

The tube will then be removed, and this part of the examination will be complete.

Part 2: 24 hours duration

A second thinner plastic tube will be passed down in the same way as the first. This tube will come out of your nose, and be secured in place using medical tape.

The tube will be attached to a recording device, which is worn on a belt. This tube will stay in place for 24 hours to record the acid levels in your gullet. It may feel strange at first, but you will get used to the feeling, and eventually not notice the tube being there.

You may feel nervous when you come in for this procedure, but the vast majority of patients tolerate the test with little problem.

If you have any difficulty passing the tube, or you are unable to tolerate the procedure, we will stop the test.

After your test 

You will be shown how to record events on the recording box such as eating, sleeping or symptoms. If you forget to record any events, you can simply write down the timing of the events on a piece of paper and return it with the recording device.

As your throat will have been numbed with an anaesthetic spray, you should wait 30 minutes before eating or drinking. You can drive home straight away, as you will not have received any sedation.

While the tube is in place, you should keep to your normal daily routing as much as possible (eating, drinking, working and moving normally). The equipment will not prevent you from doing normal activities.

Please ensure the recording device does not get wet by avoiding bathing or showering until the probe is removed.

Removing the tube

After 24 hours the display on the recording device will show Recording Complete. At this point the test is finished, and the tube can be removed.

We ask you to remove the tube yourself. This does not require any medical expertise. Simply remove the medical tape securing the tube to your face and pull the tube out. It may be a little uncomfortable.

The tube can also be removed by a relative or friend if you prefer. The tube can then be thrown away.

You do not need to press any buttons on the recording box or switch it off. Please return the recording box to the Diagnostic Centre, 2nd Floor Lift Bank B on the next working day (Monday to Friday, 8am–6pm). 

When will I know the result?

The recording needs to be carefully analysed before a diagnosis can be made.

We will send you and your GP a copy of the final report, usually 2–4 weeks after the test.

1. Endoscopy Governance Team 2. Dr Kinesh Patel (Consultant Gastroenterologist) 3. Dr Ibrahim Al Bakir (Consultant Gastroenterologist) 4. Dr Daniel Galloway (Consultant Gastroenterologist) 5. Dr Neerav Joshi (Endoscopy Clinical lead / Consultant Gastroenterologist) Camelia King-Martey