KISS: Green Inhaler Prescribing

Thank you to the authors of this guide: Drs James Smith, Aarti Bansal, & Joe Barron-Snowdon, from Greener Practice; edits and inhaler costs by NB Medical. For FAQs and QI ideas see www.greenerpractice.co.uk. See the Traffic Light tables below for the relative carbon footprint of inhalers.

Inhalers account for 3-4% of the whole NHS carbon footprint. Metered dose inhalers (MDIs) use hydrofluoroalkanes (HFA) propellants which are potent greenhouse gases, 1000 – 3000 times more potent than carbon dioxide. In the UK approximately 70% of inhalers used are MDIs which is much higher than many other European countries, and most short acting beta-agonists (SABA) are prescribed as MDIs. Salbutamol accounts for the majority of the carbon footprint associated with inhalers.

KISS: How to Reduce Inhaler Carbon Footprint

1. Optimize asthma and COPD care

• The clinical and environmental harms of poor disease control will likely outweigh any benefits from the use of different inhalers.
• The Greener Practice Team have produced an excellent “Visual Aid for Optimising Asthma Reviews” in adults and children >12 which focusses on improving care and incorporates sustainable device choices in to the annual review.
  • Find it near the top of the Resources page
• NB: on the Hot Topics course we have recently discussed:
  • Over-use SABA in asthma is extremely common and a marker of poor control and risk factor for exacerbation and death. 
    • Patients should need SABA no more than 3x/wk, or 2 inhalers/year. 
  • International asthma guidelines now recommend SABA monotherapy should be avoided and use of combined maintenance & reliever therapy using a formoterol LABA/ICS inhaler may be more appropriate as the addition of steroid lowers the risk of exacerbation & long-term airway changes. 
• Optimising asthma & COPD care will inevitably lead to ↓ salbutamol MDI inhaler requirement.

2. Use dry powder inhalers or soft mist inhalers as preferred choice when clinically appropriate

• DPI and SMIs can be used as long as patients have sufficient inspiratory flow. This may be too low in certain groups, e.g. younger children and the very elderly, and during severe exacerbations, when MDI via a spacer is more appropriate.
• Patient choice and clinical judgement remains crucial, NICE has a useful Patient Decision Aid.
  • Refer to your local guidance. Where DPIs or SMIs are not a recommended 1st line option engage with the local prescribing team about why and see if the guidelines can be updated.

3. If MDIs are needed choose a brand and regime to minimize carbon footprint

• Avoid using branded Ventolin Evohaler 
  • Ventolin Evohaler has more than double the carbon footprint of other Salbutamol MDIs, e.g. Salamol. Prescribe by brand, not generic. Lower carbon MDI options such as Salamol or Airsalb are equivalent price. (NB: this does not apply to Ventolin Accuhaler, a DPI.) 
• Prescribe inhaled corticosteroids to minimize the number of puffs required for the same dose.
  • For example, prescribe 1 puff of 200mcg Clenil twice a day rather than 2 puffs of 100mcg Clenil twice a day. This can effectively halve the carbon footprint of treatment.
• Avoiding using MDIs containing HFA227ea when clinically appropriate
  • HFA227ea has a much higher carbon footprint than the HFA134a used in other MDIs. 
  • These are Flutiform and Symbicort MDI. (NB: not Symbicort Turbohaler which is a DPI.)
• Metered dose inhalers (MDIs) are most effective when used with spacers. Let's encourage patients to use these every time, not just when they have a flare of asthma.

4. Ask patients to return all used inhalers to pharmacies for disposal

• Inhalers should not be put into household waste as this allows release of remaining HFAs into the atmosphere. Incineration thermally degrades HFAs into far less potent greenhouse gases. Some pharmacies may have access to inhaler recycling which allows the plastics and gases to be recycled.

NB: cost is always a consideration for clinicians but DPIs are not always more expensive than MDIs. 

For many combination inhalers, the cheapest DPI equivalent may be cost-saving vs MDI, while some common brands such as Symbicort and Fostair have directly equivalent MDI and DPI versions at the same price. 

The cheapest salbutamol DPI is approx. 2x the price of the cheapest MDI (e.g. Ventolin 100 Evohaler MDI NHS indicative price Feb 2021 is £1.50 vs Easyhaler 100 DPI is £3.31) although still cheaper than many MDIs. Even then this cost is small in comparison to the £20-60 of many combination inhalers, while having a 10-30x smaller carbon footprint and dwarfed by savings from optimising care, reducing SABA overuse, consultations and treatment for exacerbations and hospitalisations.