Nitrous oxide

Disclaimer: This fact sheet is for education purposes only. Please consult with your doctor or other health professional to make sure this information is right for your child.

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What is Nitrous Oxide?

You may know this gas as happy gas or laughing gas. It is a sweet smelling, colourless gas used to ease pain and anxiety (often given at the dentist, or to ease the pain of labour).

How will it help my child?

Your child may be offered nitrous oxide gas while the doctor or nurse carries out a procedure such as stitches, dressings or a blood test. The gas helps to ease the pain and anxiety your child may feel, but usually does not make them fall fully asleep.

When your child starts to breathe the nitrous oxide, they will feel drowsy within a couple of minutes. The gas will be continued until the procedure finishes and will wear off quickly when the gas is stopped. This means your child can quickly get back to their usual activities (playing, eating etc).

How will it be given?

Nitrous oxide will be given by a nurse or doctor. Before it is given, your child will be assessed to make sure this is the best option. You will be asked to make sure your child stops eating and drinking for a certain time before they have the gas (usually at least two hours, but may be longer if other sedating medicines will be used with the nitrous oxide). This helps reduce the risk of vomiting.

Your child will be given a mask or a mouth-piece attached to a machine through which they will breathe the gas. It can be helpful to look at, and play with the mask with your child before the procedure starts so your child is comfortable with it before it is placed on their face.

You are welcome to stay while your child is having the gas. The best thing you can do is to stay where your child can see you and hold their hand. The gas will be given a few minutes before the procedure starts and will continue until it is finished. The gas may make your child feel "floaty", warm and tingly. Your child may or may not remember anything about the procedure.

When the nitrous oxide is stopped, your child will then be given oxygen through a mask to clear the gas from their lungs; this last stage in which only oxygen is given is very important. After your child has had the oxygen and is awake and alert they will be able to eat and drink normally.

Are there any risks?

This gas is safe for use in children and there are no long-term side effects from occasional use.

Young children may not like having a mask on their face. They may feel angry or confused by the mask and gas and will need you to stay close and comfort them. The nurse or doctor may need to hold the mask firmly over your child's face at first until the gas starts to work and your child relaxes.

Other side-effects may occur, but they are usually minor and get better quickly. Some children feel sick or vomit during nitrous oxide sedation, and some may have wheezing or other breathing problems. The staff looking after your child will know how to manage these problems if they occur.

What can I do to help?

Hospitals can be frightening places for children. If a child feels sick or is in pain, it can be upsetting to have nurses and doctors whom they don't know look after them. We encourage parents to stay with their child to look after and comfort them during and after most procedures. If your child asks about the procedures being done, reassure them and explain in simple terms what is being done and why. Always tell the truth.

At times it is helpful to tell stories, talk about the family or anything else that may help to take their mind off the procedure. Remain calm; if you get upset so will your child. The staff are there to help you and your child. If you would like more information please ask the nurse or doctor caring for your child.


  • It helps to be near and to comfort your child during the use of nitrous oxide.
  • This gas is safe for use in children and there are no long term side effects.

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Kids Health (CHW)
The Children's Hospital at Westmead
Tel: (02) 9845 0000
Fax: (02) 9845 3562
Sydney Children's Hospital, Randwick
Sydney Children's Hospital, Randwick
Tel: (02) 9382 1688
Fax: (02) 9382 1451
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Kaleidoscope Children Young People and Families Network
Tel: (02) 4921 3670
Fax: (02) 4921 3599