How switching a handful of patients’ inhalers saved nearly 5,000kgCO2e

While switching inhalers may not be for everyone, reviewing patients who may benefit from a lower carbon device could have an enormous impact.
Inhaler shaped car with smoke coming out of it against a city skyline

Awareness of the impact of human activity on our environment is growing, with heatwaves, flash floods, forest fires and eco-activism regularly dominating the headlines. The climate crisis is a health crisis and, without urgent action, the effects on our health and planet will be devastating.

In 2020, the NHS revealed its ambition to become the world’s first carbon neutral national health service. Its report ‘Delivering a ‘net zero’ National Health Service‘ makes for interesting reading: the NHS accounts for around 4% of the UK’s total carbon emissions and roughly 25% of the NHS’s emissions are attributed to medicines.

Around 3% of the NHS’s carbon footprint is produced from just one type of medicine — inhalers — the main driver being the propellant gas contained within pressurised metered dose inhalers (pMDI).

To mobilise action in this area, NHS England included two environmental sustainability indicators within the primary care network (PCN) ‘Investment and Impact Fund‘, which focus on driving down the percentage of pMDI’s as a proportion of all non-salbutamol inhaler prescriptions and reducing the average carbon emission of all prescribed salbutamol inhalers.

A cultural change in our prescribing habits could benefit the environment without compromising patient care

The UK is an outlier when it comes to its use of pMDIs. Here, they make up around 70% of the inhalers used, while in other parts of Europe, such as Scandinavia, they rely predominantly on dry powder and soft mist inhalers. Health outcomes in those regions are not drastically different, suggesting that a cultural change in our prescribing habits could benefit the environment without compromising patient care.

Julie Hyam, lead respiratory nurse, explained how she transformed prescribing over an 18-month period during a global pandemic. In an ideal world, we invite people into the GP surgery, have an open and honest discussion and, if they are happy to do so, we assess their inhaler technique.

But we are living in a pandemic, with strict infection prevention controls and a cohort of patients who are quite rightly fearful.

Hyam had been speaking to suitable patients over the phone and agreeing a trial. She then texts out the Asthma UK demonstration video and follows up with another call after a couple of weeks.

Patients are often very happy to try a different inhaler, providing it is safe, effective and they know they can switch back if the change does not suit them.

One particularly invaluable tip Hyam shared was that she only prescribes one reliever inhaler. Many patients want spare inhalers; however, she believes the one inhaler should go wherever they go, much like a mobile phone.

Armed with these tips and a PowerPoint presentation, I ambushed my fellow clinicians at each of the practices within the North Oxfordshire Primary Care Network during their clinical meetings.

Many of them had heard about this issue before but were shocked by the emissions figures. I personalised the facts by working out that a 175-mile car journey (emissions equivalent to one pMDI) gets you from Oxford to Liverpool, while a DPI only produces emissions equivalent to a four-mile journey, which, as I described it, is only halfway to the next village.

I also brought some pMDIs to illustrate that the equivalent CO2 emissions from three tiny inhalers combined weigh more than my own body weight.

I then reached out to my PCN community pharmacies to inform and prepare them for the switches and ‘New medicines service’ referrals to come. My community pharmacy PCN lead, Yasin Jussab, has been invaluable as a sounding board and the community pharmacy safety net has assured me that the patients I switch will receive additional support and be referred back if they experience any problems.

I then set to work tackling the most prolific prescribers of pMDI’s in the PCN. I ran a search of all registered patients aged 12 years and above who were currently prescribed a pMDI.

The reason for this wide age range was to ensure I didn’t exclude people who might be capable of using a DPI, purely because of a cut-off age or a ‘frailty’ label. There might need to be more nuance and caution, but I feel it is important to be inclusive.

I screened the first 20 patients, running through the practicalities of which switches I could make within our formulary and the restrictions of licensing and indication. At this point, I felt familiar and comfortable enough with switches to think on my feet. At the end of January 2022, I invited patients to book in for a review to discuss changing their inhaler.

It is imperative that switching inhalers is a shared decision based on the evidence, the clinician’s experience and the patient’s lived experience

It is imperative that switching inhalers is a shared decision based on the evidence, the clinician’s experience and the patient’s lived experience. The most environmentally friendly inhaler is the one that a patient uses properly to keep them healthy and out of hospital. Patients should be actively involved in their care, which is why wholesale switches by letter or text message is abhorrent to me.

In my first two clinics, I reviewed 18 patients. Of these, 14 agreed to a trial of a lower carbon alternative and, so far, none have reported any difficulties. One patient declined because they felt that their condition was well-controlled and did not want to learn a new inhaler technique. The other three conversations resulted in a shared decision that a trial was inappropriate at this time but would be reassessed in the future.

Over the next 12 months, the 14 agreed switches could amount to a saving of 4,740kgCO2e — about the same as 15 economy class flights from London to New York. And this is just the beginning.

Top tips for healthcare professionals:

  • Tailor your message to your audience;
  • Assess if ‘Maintenance and Reliever Therapy’ (MART) is appropriate — this can reduce additional reliever inhalers;
  • If prescribing a reliever inhaler, make it just one reliever inhaler at a time;
  • If prescribing multiple inhalers, try to keep them the same so that the technique is the same;
  • In asthma, consider leukotriene receptor antagonist (LTRA) therapy;
  • Make the doses work for the patient, i.e. instead of beclometasone 100mcg two puffs twice daily (lasts 50 days), prescribe beclometasone 200mcg one puff twice daily (lasts 100 days and halves emissions);
  • Local collaboration in action — find your local ‘Greener Practice’ group here: Local Groups — Greener Practice;
  • Monitor your performance on OpenPrescribing.

Brendon Jiang is a senior clinical pharmacist based in Oxfordshire and a member of the Royal Pharmaceutical Society Primary Care Expert Advisory Group

Last updated
The Pharmaceutical Journal, PJ, March 2022, Vol 308, No 7959;308(7959)::DOI:10.1211/PJ.2022.1.132140


  • Babir Malik


  • Kyle Curd

    Really interesting stuff! Will have to keep an eye on this in practice. Thanks so much!

  • Jag Shur

    An excellent clinical perspective on inhaler switching.


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