Gas and Air

Advantages and Disadvantages of Gas and Air

Gas and air, also known as “laughing gas” or Entonox, is often used by women for pain relief during labour.

Although it won’t get rid of labour pains completely, it will certainly reduce the pain and about 80% of women use it, making it by far the most common method of relieving pain in labour.

What is gas and air?

Gas and air is a mixture of oxygen and nitrous oxide gas, which can be supplied in cylinders (in the case of a home birth, for example) or pumped from a central supply, as is more often the case in a hospital setting.

How to use gas and air

You are in control of the gas and air and can use it throughout your labour.

You’ll be given your own mouthpiece or a mask, which is used to deliver the gas, and your midwife will show you how to use it. You may also have the opportunity to try it an antenatal class.

As you breathe in the gas and air you may feel a little lightheaded and giggly – it takes about 20 seconds of slow, deep breathing to get enough gas and air into your system, and it can take a few minutes to feel the full pain relieving impact.

It’s best to start taking the Entonox as soon as a contraction is beginning so that you get the maximum pain relief when the contraction is at its strongest.

Between contractions it’s best to have a break from the gas and air – if you take it constantly for long periods it can make you feel more lightheaded or dizzy.

What are the advantages of gas and air?

  • It's easy to use

  • It reduces the pain (although it doesn’t take the pain away fully) It doesn't stay in your system; as soon as you stop breathing it in, your lungs clear out all the gas and air in your system and if you have any side effects then they will stop too

  • It's under your control

  • It's flexible and quick-acting

  • It's perfectly safe for your baby

  • You and your baby won’t need extra monitoring while you're using it

  • You can use it in the water if you want to labour in a birth pool or in the bath

  • there are no harmful side effects for mother or baby

What are the disadvantages and side effects of gas and air?

  • It is only a mild painkiller

  • It can make some people feel drowsy, light-headed or sick

  • It may dry out your mouth if you use it for too long

  • Keeping hold of the mouthpiece or mask may prevent you from moving around and getting into a comfy position

  • It sometimes takes a little while to get the timing right so that it's effective when your contractions peak

  • It may make you feel even more drowsy if you use gas and air with a stronger pain relief drug like pethidine or morphine

How does gas and air work?

Gas and air works by making you feel light-headed and almost euphoric. Your mind will not be on the pain at all. In fact, you may well find yourself speaking nonsense. Once you stop inhaling the gas and air, you will find that the effects wear off very quickly: in most cases after 15 minutes.

Can you buy gas and air?

No, entonox is a restricted medical product and even though you’ll find some websites offering it for sale, they can’t sell it to the general public.