Entonox
For your endoscopic procedure
What is Entonox?
Entonox is a well-established pain-relieving gas made from two gases. These gases are 50% nitrous oxide and 50% oxygen. Entonox is used to relieve pain when having surgical or medical treatments (endoscopy). It is self-administered, which gives you complete control over the timing of your pain relief.
Before your procedure commences, your endoscopy nurse will inform you how to use the Entonox correctly.
You will be given a mouthpiece for the administration of the Entonox.
- You will be shown how to hold the mouthpiece between your teeth and close your lips around it
- You will then need to breathe in and out through your mouth. You do not need to take it out of your mouth
It is important that you concentrate on breathing normally throughout the procedure. You may practice using the Entonox before your procedure starts.
Your nurse will advise you when to start using the Entonox. It will remain by your side throughout the procedure.
Take at least four breaths before the procedure starts. Continue to use the Entonox as and when you need. If you find the Entonox is not satisfactory at any stage, inform your nurse. It may be possible for other pain relief to be given to you.
Entonox takes about 20 seconds to take effect, with full relief after approximately one minute. It is important to continue using the Entonox by breathing in and out normally, as you may need it throughout your procedure.
You may experience common, mild side effects whilst using the Entonox but these usually disappear once you have stopped using it.
These may include:
- Light headedness whilst using the Entonox
- Disorientation
- Nausea (feeling sick)/sickness
- Tiredness
- Dry mouth
- A tingling sensation, usually in the fingers, which can be due to the over-breathing of Entonox
- Air trapped or lodged in an artery
Entonox works only when you breathe in. It wears off very quickly (normally within a couple of minutes) once you have stopped breathing it in. However, you should rest for about 30 minutes before you start to walk around again.
You can drive/operate machinery 30 minutes after using Entonox.
You should then be ok to carry on with the rest of your daily activities with no problems.
Entonox is normally available if you wish to use it, but it is not suitable for everybody. Your nurse/doctor will assess your suitability first.
Do not use Entonox if you have:
- Severe breathing problems/COPD
- Recently undertaken an underwater dive (48 hours)
- Head injuries or injuries to your face and jaw
- A collapsed lung
- A severely bloated stomach
- Known increased pressure on the brain
You may not wish to use Entonox at all. If this is the case, your nurse/doctor will discuss other methods of pain relief with you.
If you have any other queries or concerns, please speak to a member of the team on your admission to the hospital.