Entonox®

Entonox® (also known as gas and air ) is a mixture of nitrous oxide and oxygen used to relieve pain.  

Entonox® is a gas you breathe in via a mouthpiece or facemask when you need it. You're in control of the amount of Entonox you use. To get the best effect, it is important to get the timing right. You should start breathing Entonox® as soon as you feel a contraction coming on to get the full effect. Stop using Entonox as the contraction ends, breathing normal air between your contractions.

Entonox® is the most common pain relief for labour. It will not take the pain away completely, but people like it because:
·    It may help you feel more relaxed
·    It has no harmful effects on your baby
·    You can use it at any time during labour
 

Entonox® has been used safely for pain relief for labour for many years.  The common side effects are generally mild and go away quickly when you stop using it. These include:
·    A dry mouth
·    Feeling sick (nausea) and vomiting
·    Feeling dizzy, light-headed or sleepy
 
Having a break from using Entonox in between contractions helps to reduce these unwanted effects.

Entonox® is a greenhouse gas and contributes to global warming. Maternity wards are using new technology to break it down into harmless gases. This helps reduce its impact on the environment. To learn more, see our information on your pain relief for labour and the environment.
 
Long-term exposure to high levels of Entonox® may cause health problems. This is not a concern for those using it for a few hours during labour but could affect healthcare workers. Maternity units must track Entonox® levels to keep staff safe. In rare cases, if levels are too high, its use may be paused. If this happens, other pain relief options are available.