Nitrous oxide for pain

This leaflet is for parents and carers about how to use this medicine in children. Our information may differ from that provided by the manufacturers, because their information usually relates to adults. Read this leaflet carefully. Keep it somewhere safe so that you can read it again.

Name of medicine

Nitrous oxide

Common brands: Entenox, Equanox

This leaflet is about the use of nitrous oxide gas to provide pain relief during a short medical or surgical procedure.

Why is it important for my child to take Nitrous oxide?

Nitrous oxide will help your child to feel less pain during a short medical procedure (such as having a dressing changed).

What is Nitrous oxide available as?

Nitrous oxide is a gas. It comes in a metal canister and is mixed with oxygen.

When should I give Nitrous oxide

Your child should start to breathe in nitrous oxide a few minutes before the procedure is started.

How much should I give?

Your child should have as much nitrous oxide as they need to cope with the pain of the procedure.

How should I give Nitrous oxide?

Gas to breathe in

  • The Nitrous oxide should only be used with the support of people who have been trained in its use.
  • Your child will be shown how to breathe Nitrous oxide in through a special face mask or mouthpiece. Your child should hold the face mask or mouthpiece themselves, so that they can control when they breathe in Nitrous oxide.
  • If your child breathes in too much Nitrous oxide, they will become very drowsy (sleepy), and they probably will let the face mask or mouthpiece fall away from their face. As they breathe out the Nitrous oxide they will begin to feel more awake again. They may then want some more Nitrous oxide to help with the pain. Let your child decide when this is.

When should the medicine start working?

Nitrous oxide will start to provide pain relief within a few minutes.

What if my child is sick (vomits)?

  • Some children feel sick or are sick (vomit) after breathing in nitrous oxide. This feeling should pass quickly once they stop breathing in the gas.
  • When they have recovered they can have more nitrous oxide if they need it.

What if I give too much?

If your child breathes in too much nitrous oxide, they will become very drowsy and may start to lose consciousness. They will probably let the face mask or mouthpiece fall away (or you could move it away). They will breathe out the nitrous oxide over the next few breaths and become more awake again.

Are there any possible side effects?

Your child may get a headache, feel dizzy or sick, or be sick (vomit). These symptoms should pass quickly once your child stops breathing in the gas.

There may sometimes be other side effects that are not listed above. If you notice anything unusual and are concerned, contact your doctor. You can report any suspected side effects to a UK safety scheme at

Can other medicines be given at the same time as Nitrous oxide?

  • Tell the person who provides the nitrous oxide about any medicines your child is taking.
  • Nitrous oxide can be given at the same time as other medicines used for pain relief, such as paracetamol, ibuprofen and local anaesthetics.

Is there anything else I need to know about this medicine?

  • If your child has had an accident or injury recently, tell the person who is doing the procedure, before your child has any nitrous oxide.
  • When taken often, there is a low risk that nitrous oxide can affect the blood. The doctor or nurse who provides the nitrous oxide will keep a record of how often your child has had nitrous oxide. They may want to do blood tests to check for problems.
  • You can help by keeping a record of when your child has nitrous oxide.

Who to contact for more information?

The person who provides the Nitrous oxide will be able to tell you more about it, and about other medicines used to help with pain.

England: NHS 111

Tel 111

Scotland: NHS 24

Northern Ireland: NI Direct

Wales: NHS Direct

Tel 111 (free) or 0845 46 47 (2p per minute)

Copyright disclaimer

Version [2]. © NPPG, RCPCH and WellChild, all rights reserved. Review by March 2016.

The primary source for the information in this leaflet is the British National Formulary for Children. For details on any other sources used for this leaflet, please contact us through our website,

We take great care to make sure that the information in this leaflet is correct and up-to-date. However, medicines can be used in different ways for different patients. It is important that you ask the advice of your doctor or pharmacist if you are not sure about something. This leaflet is about the use of these medicines in the UK, and may not apply to other countries. The Royal College of Paediatrics and Child Health (RCPCH), the Neonatal and Paediatric Pharmacists Group (NPPG), WellChild and the contributors and editors cannot be held responsible for the accuracy of information, omissions of information, or any actions that may be taken as a consequence of reading this leaflet.