Anaesthetics and inhalers

In the NHS, some of the most carbon intensive products are asthma inhalers and anaesthetic gases. These account for four and two percent of our overall carbon footprint respectively. 

A single inhaler can have the same carbon impact on the environment as a 180 mile car journey (there are 5.4 million people in the UK suffer from asthma).  An hour of using one of the most carbon intensive anaesthetics has the carbon footprint of a 230 mile car journey.

The NHS is working to:

  • Reduce the carbon impact of anaesthetics by at least 40% by 2028
  • Reduce the carbon impact of inhalers by at least 50% by 2028.


Some anaesthetic gases are also powerful greenhouse gases. Two gases; desflurane and nitrous oxide, make up 96% of the total impact. Desflurane is an anaesthetic gas used in surgery which has a climate change impact 2,540 times worse than carbon dioxide. Nitrous oxide, used in ambulances, emergency departments, maternity and surgery, is less damaging, however it is used in large amounts across the NHS.

This work has the support of the Association of Anaesthetists and groups representing midwives, paramedics and emergency medicine to ensure that health care professionals are aware of how impacts can be reduced.

Clinicians can help reduce impacts immediately through:

  1. Anaesthetists can consider a change from high carbon desflurane to low carbon sevoflurane. 
  2. Use low flow anaesthesia, e.g. ≤1 l/min
  3. Where clinically appropriate reduce unnecessary use or waste of nitrous oxide


The annual carbon footprint of inhalers prescribed in England is larger than that produced by many small countries.  This is because the propellant gases used in pressurised inhalers are powerful greenhouse gases, up to 3,350 times more damaging than carbon dioxide. 

The impact of an individual patients’ inhaler use in one year can be the equivalent to driving 2,000 miles in a typical car [3 Ventolin relivers inhalers at 28kg each and 12 controllers per year at 19kg each]. In the UK around 70% of prescribed inhalers use propellants, the rest are propellant-free Dry Powder Inhalers or reusable Soft Mist Inhalers. 

But there are alternatives – in most cases, powder-based inhalers are just as clinically effective and have a small fraction of the environmental impact. Currently they make up 90% of inhalers prescribed in Sweden. It is about giving patients informed choice about the care they receive and their medicines

The Royal Pharmaceutical Society, Royal College of General Practitioners and British Thoracic Society, along with other national clinician and patient groups are working with the NHS. Industry is also developing low carbon propellants and alternatives to reduce emissions. 

Clinicians can help reduce impacts immediately through:

  • Offering lower carbon or propellant free alternatives where clinically appropriate (For example Dry Powder and reusable Soft Mist inhalers are very low carbon).
  • Ensuring patients know how to use their inhaler properly and are having regular reviews.
  • Ensuring patients know to return used inhalers to their pharmacy to be disposed of in an environmentally safe way