A person holds up a blue inhaler and shows it off.
Dry powder inhalers and aqueous mist inhalers can help reduce a user’s carbon footprint, according to researchers. (For Spectrum Health Beat)

Eco-friendly asthma inhalers could lower both greenhouse emissions and medical costs, according to a new British study.

Inhalers use hydrofluoroalkane propellants to atomize and pump out the medication, but hydrofluoroalkane are potent greenhouse gases.

And metered-dose inhalers are responsible for 3.9% of the carbon footprint of the National Health Service in the United Kingdom, the study authors noted.

Effective green alternatives are available, such as dry powder inhalers and aqueous mist inhalers.

University of Cambridge researchers used National Health Service prescription data from England in 2017 and carbon footprint data on inhalers commonly used in England to compare the environmental and financial impacts of different inhaler types.

The carbon footprints of metered-dose inhalers were 10 to 37 times higher than those of dry powder inhalers, according to the study published recently in the journal BMJ Open.

At 2017 prescription levels, replacing 1 metered-dose inhaler in 10 in England with the cheapest equivalent dry powder inhaler would have reduced carbon dioxide emissions by 58 kilotonnes. That’s equal to 180,000 car trips from London to Edinburgh—each about 400 miles.

The change would also have saved an estimated $10.5 million in drug costs a year, researchers estimated.

At the individual level, each metered-dose inhaler replaced by a dry powder inhaler could save the equivalent of 330 to 882 pounds of CO2 a year.

That’s similar to many carbon-reducing actions people take at home, such as adding insulation, recycling or cutting out meat.

“Any move towards ‘greener’ inhalers would need to ensure that replacements were cost-effective,” said Dr. Alexander Wilkinson, a consultant in respiratory medicine at East and North Hertfordshire National Health Service Trust in Stevenage, England.

“By switching to less expensive brands, we’ve shown that it would still be possible to make a positive impact on carbon emissions while at the same time reducing drug costs,” he said in a Cambridge news release.

Wilkinson said patients should not abruptly stop their usual treatments in order to reduce their carbon footprint.

“Instead we recommend patients review their condition and treatment at least annually with their health care professional and at this point discuss whether a more environmentally friendly inhaler is available and appropriate in their situation,” he advised.