Asthma and COPD patients rely on inhalers to breathe easier, but a groundbreaking study reveals these life-saving devices are contributing significantly to global warming. In the United States alone, inhalers emit greenhouse gases equivalent to over 530,000 cars annually, raising urgent questions about sustainable healthcare solutions.
The Environmental Toll of Inhalers
A decade-long study by researchers from UCLA and Harvard, published in the Journal of the American Medical Association (JAMA) in October 2025, analyzed the carbon footprint of inhalers used for asthma and chronic obstructive pulmonary disease (COPD). The findings are stark: between 2014 and 2024, inhalers used by patients with Medicaid, Medicare, and commercial insurance in the US generated 24.9 million metric tons of carbon dioxide equivalent—matching the emissions of 530,000 cars each year.
Metered-dose inhalers (MDIs), commonly known as “puffers,” are the primary culprits, responsible for 98% of these emissions. These devices rely on hydrofluoroalkane (HFA) propellants, potent greenhouse gases, to deliver medication. In contrast, dry powder inhalers (DPIs) and soft mist inhalers (SMIs) produce negligible emissions. DPIs use a patient’s breath to release medication, while SMIs convert liquid into a fine spray, eliminating the need for harmful propellants.
Why Metered-Dose Inhalers Dominate
Despite the availability of eco-friendly alternatives, MDIs remain the go-to choice in the US due to medical and systemic factors. Young children often require spacers—devices that ensure proper medication delivery to the lungs—which are only compatible with MDIs. Similarly, frail older adults with reduced lung strength may struggle to use DPIs, which require stronger inhalation. However, the study emphasizes that most patients could effectively use DPIs or SMIs without compromising treatment outcomes, as demonstrated in countries like Sweden and Japan.
The dominance of MDIs is also tied to market dynamics. In the US, greener alternatives like dry-powder albuterol are often not covered by insurance, making them cost-prohibitive for many. Additionally, some widely used drugs, such as budesonide-formoterol, are available in dry-powder form in Europe but not in the US, limiting patient options.
A Call for Systemic Change
The study’s lead author, a UCLA pulmonologist, stressed that the goal is not to shame patients but to push for systemic reforms. “Patients with asthma and COPD shouldn’t bear the burden of this environmental impact,” he noted. “It’s up to policymakers, insurers, and healthcare systems to make sustainable options accessible and affordable.”
New low-emission MDIs are expected to hit the US market soon, but their high costs as brand-name products could exclude patients with limited insurance coverage. Experts warn that without policy changes, such as expanding insurance coverage for DPIs and SMIs or incentivizing manufacturers to prioritize greener options, the environmental toll will persist.
Global Lessons and Local Solutions
Countries like Sweden and Japan offer a blueprint for reducing inhaler-related emissions. By prioritizing DPIs and SMIs, these nations have maintained high-quality care while slashing their carbon footprint. The US could follow suit by:
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Expanding Insurance Coverage: Ensure DPIs and SMIs are covered under Medicaid, Medicare, and private plans to reduce out-of-pocket costs.
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Promoting Research and Development: Encourage pharmaceutical companies to develop and distribute low-emission inhalers tailored to the US market.
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Educating Healthcare Providers: Train doctors to recommend greener inhalers for eligible patients, reducing reliance on MDIs.
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Policy Advocacy: Implement regulations that incentivize sustainable manufacturing practices and penalize high-emission products.
Balancing Health and the Environment
The intersection of healthcare and environmental sustainability is a growing concern as climate change accelerates. Inhalers are just one piece of the puzzle, but their significant emissions highlight the need for innovation in medical technology. Patients deserve access to treatments that safeguard both their health and the planet.
As the US grapples with this hidden climate impact, collaboration between policymakers, insurers, and healthcare providers is critical. By adopting greener inhalers and addressing market barriers, the nation can protect millions of patients while reducing its carbon footprint.
