Inhalation sedation

Sedation for dental treatment

Inhalation sedation involves breathing a gas that helps you feel calm and relaxed during your dental treatment.

Once you are sedated, you will be given a local anaesthetic injection which will numb your mouth. This is not a general anaesthetic, and you will be awake for your treatment.

You might want to bring a responsible adult with you to your appointment. This is not always needed.


The dentist will tell you if you need to have an adult with you to take you home.

Preparing for inhalation sedation

  • Do not bring any children or babies to hospital with you, as we do not have a suitable space for them to wait.
  • If you have a cold or feel unwell before your treatment, or think you might be pregnant, please call us for advice.
  • Please arrive for your appointment on time, as we might not be able to see you if you arrive late.

Your medicines

Your medicines will be reviewed before your appointment. You will be told if you need to stop any of them for a short time before your treatment.

  • Unless you are told not to, please take your regular medicines as usual.
  • Let your dentist or nurse know if you have allergies to any medicines.

Eating and drinking

  • You do not need to stop eating before inhalation sedation.
  • Have a light meal before your appointment. 

Having inhalation sedation

  1. Your dentist will explain the planned treatment, and check that you understand what will happen.
  2. The dental nurse might take your blood pressure.
  3. You will be asked to lie back in the dental chair.
  4. You will be given a mask to put over your nose.
  5. The dentist will then give the sedation gas slowly, and will ask you to relax.
  6. The dental team will monitor your breathing and how relaxed you are during treatment.
  7. Your dentist will give you an injection of local anaesthetic to numb the area where you will be having treatment.

You might feel a slight stinging sensation when you have local anaesthetic, but then the area should feel numb. Please let your dental know if you feel any discomfort.

Risks of inhalation sedation

Inhalation sedation is very safe.

As you breathe the gas you might feel dizzy or light-headed. If you feel uncomfortable, please let the dental team know.

You will be given oxygen to breathe at the end of the treatment to help you feel more alert.

Your medical team will speak to you about risks in more detail when you sign the consent form.

There are alternatives to inhalation sedation, such as sedation through a vein in your arm or hand (intravenous sedation) or a general anaesthetic.

After inhalation sedation

At the end of treatment, you will be taken to the recovery area.

You will still feel relaxed, and many people feel unsteady on their feet.

For these reasons, you cannot leave hospital until you have been checked by the dentist or dental nurse.

Most people spend about 10 minutes in the recovery area.

Follow-up appointment

If you need a follow-up appointment, your dentist or dental nurse will let you know. You will either be given an appointment by the reception team, or put on the waiting list and sent a letter when an appointment is available.

Recovering from sedation at home

For your safety, it is important that you follow the advice below when you are at home after having inhalation sedation.

Although you might feel fine, your reasoning, reflexes, judgement, coordination and skill can be affected by the sedation until the next day.

Please rest at home until the next day


  • drive any vehicle, or ride a bicycle
  • operate any machinery, including domestic appliances
  • attempt to cook, use sharp utensils or pour hot or boiling liquids
  • drink alcohol or smoke
  • take sleeping tablets
  • make any important decisions or sign any contracts
  • use the internet
  • be responsible for children or other dependants

Please follow this guidance for 48 hours after having sedation.

Resource number: 2201/VER4

Last reviewed: July 2019

Next review due: July 2022

Contact us

If you have any questions or concerns about sedation for dental treatment, contact the Department of Sedation and Special Care Dentistry.

Phone: 020 7188 6066 Monday to Friday, 9am to 4.30pm

You can also contact the dental day surgery unit.

Phone: 020 7188 1810 Monday to Friday, 9am to 5pm

Address: 26th Floor, Guy’s Tower, Guy’s Hospital

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