Also known as Gas and Air, or laughing gas, Entonox, is made up of 50% each of Nitrous Oxide and Oxygen. This is usually available at every bedside in a labour ward and is self –administered through a mouthpiece or facemask. It has a 2 way valve that lets you breathe in and out through the mouthpiece. It has a calming effect and helps to take the edge off the pain rather than eliminate it completely
It takes up to 20 seconds to start to work, so in order for it to be effective in helping with your pain, you must start to take it at the very start of your contraction.
It is very safe for mother and baby as it does not pass over the placenta.
It can be useful for relatively short periods of time- perhaps an hour or two but is not ideal for longer term use.
You cannot overdose on Gas and Air- although it does have a slight cumulative effect, it will be blown off within 30 seconds to a minute and you will feel completely normal again.
It can make you feel sick and dizzy the first time you try it which can be disorientating if this first time is during a painful contraction. It can be a good idea to practise sucking on the air and seeing how it makes you feel when you are not having a contraction.
It can be useful if you are having a rapid labour and is also helpful towards end of first stage of labour- just before you start pushing. It is not good to use when pushing as you should not really be breathing in and out whilst pushing. See our section on Stages of Labour- Pushing
It can be very useful to use whilst waiting for an epidural, during internal examinations, and whilst being stitched up (if you have torn) after delivery.
Many women also seem to find it useful as a focal point or form of distraction if you don’t want to have an epidural. Biting down on the mouth piece helps some women deal with the pain.
A word of note- it can leave your mouth feeling very dry afterwards so it is a good idea to take frequent sips of water whilst using Gas and Air. Some women like to chew on ice chips or suck ice cubes.