Entonox: Meaning, Benefits and Impact in Labour

Shaheen, 35 weeks pregnant, was gearing up for her delivery by exercising and focusing on a healthy diet, but still there remained a lingering fear about labour pain. She read up about how to reduce labour pain and options for a painless delivery. It was then that she came across Entonox, a mixture of gases. She was keen to know about entonox uses, composition, etc. but could not find enough information online. 

She then decided to ask her gynecologist, Dr Anita Sabherwal Anand, known for her detailed consultations, about Entonox in an upcoming consultation. 

What is Entonox used for?

Entonox or laughing gas as it is sometimes called, is a mixture of two gases in equal parts. It is used to relieve pain in procedures such as tooth extraction, dressing for burns and is also used during labour. 

Shaheen was keen to know how the gas is used during labour.  

“How should I use Entonox gas in labour?” she asks. 

“When you ask for Entonox in labour, you will be given a mouthpiece through which you can breathe in the gas. The gas only works when breathed in, which is why you will have to breathe it in throughout the time you are in pain,” says Dr Anita.

“Since you will be holding the mouthpiece, you can decide how much to take in, or you can decide to stop, if you feel uncomfortable for any reason.”

A nurse trained in the use of Entonox will be watching over you while you inhale the gas.

What does Entonox do to the body?

When inhaled, Entonox acts rapidly within minutes. The gas passes through your blood into different parts of the body and helps reduce the pain felt.

Is it dangerous?

“Entonox gas is very safe and can be used throughout labour.”

How long does Entonox stay in your system?

The effect wears off after about eight minutes of inhaling the gas. It is recommended you rest for about 15 minutes before walking around. It is not advised to drive until after half an hour of breathing in the gas. 

Shaheen listened carefully and then asked whether the composition of Entonox could induce sleep.

Is Entonox a sedative?

Entonox may make you feel light-headed or drowsy but it does not usually put you to sleep. 

Now that she understood what the gas was, she was keen to know the impact of the gas.

How effective is Entonox?

“Entonox helps reduce the pain but does not eliminate the pain completely,” explains Dr Anita. “There are multiple benefits with using Entonox, which is why we recommend it if you think the pain is intense.”


Advantages of using Entonox:

  • Acts within minutes
  • Can be taken in a controlled dosage, since you decide how often you want to breathe it in
  • Can be used by most women
  • Allows you to remain mobile

“One of the great things about the gas is that it usually does not have any ill effects.”

What are the side effects of entonox?

The gas may make you feel a little drowsy. It may cause nausea or dryness in the mouth but these symptoms usually disappear when you stop inhaling the gas. In some cases, your fingers may feel slightly prickly but this may occur if you breathe in too fast. In case this happens, let the nurse know so she can guide you on breathing slowly.  

Shaheen was concerned about what would happen if in case she breathed in too much of the gas, and voiced her apprehension. 

Can you overdose on entonox? 

“Most of the time, women do not overdose on Entonox. In the rare case that this happens, it can be dealt with by shutting down the supply of the gas for a while, so there’s nothing to be worried about,” reassures Dr Anita. 

Curious about any instances in which it should not be used, Shaheen asked the doctor her question.

When should you not give Entonox?

“Entonox can be given to most women in labour provided they feel the need for it.”

It may not be advised in a few situations such as:

  • Collapsed lungs
  • Eye surgery
  • Head injuries

Happy with all the answers to her questions, Shaheen felt comfortable with her knowledge of Entonox. She went into labour at 39 weeks, endured labour till she could and used Entonox when she could not tolerate it any longer. She delivered a healthy baby girl, and was happy to initiate skin to skin contact and breastfeeding immediately at birth.

This article has been written with Dr. Anita Sabherwal Anand, Consultant, Obstetrician-Gynecologist at Sitaram Bhartia Hospital in South Delhi. Dr. Anita is a highly qualified gynecologist with 20+ years of experience who is trusted by low-risk and high-risk mothers alike for her guidance on having a healthy pregnancy and delivery.

Come in for a consultation with our gynecologists! Please call on + 91 9871001458 for appointments.