Is Your Asthma Inhaler Ruining the Environment?
According to a recent publication in the British Medical Journal, yes.
I try to do right by the environment. My family has been driving less, walking and biking more. We are avid at recyclers. We have been eating less meat. And when why fly cross-country, we do so with some pangs of carbon guilt. So imagine my dismay when I saw this headline pop up in my Google News feed:
Asthma Inhalers are as Bad for the Environment as Eating Meat.
Wait, what?!? Does the albuterol MDI that so many people rely on have a huge carbon footprint? Do you, the individual with asthma, have to choose between breathing easily and environmental destruction? How much have I, as an ER doctor prescribing boatloads of these inhalers, warmed the earth?
That first headline story was clickbait fluff, so I tracked down the referenced BMJ publication here. It is a thoughtful and smartly constructed research paper. The authors state that by upgrading your style of inhaler, you can save an amount of CO2 “roughly equivalent to installing wall insulation at home, recycling or cutting out meat.”
Is this true? If so, how much more money will it cost you, as a patient, to change inhalers?
A History of Inhalers
Patients have treated breathing problems with inhaled medications for thousands of years, and methods have varied, both in their efficacy and their carbon footprint. The first recorded inhalation treatment was by the ancient Egyptians who inhaled smoke (bad idea) from burning herbane (contains atropine, good idea). Later, big names got in on the game including Hippocrates (a proponent of herbed vinegars, which were vaped) and Pliny the Elder (yummy millipedes crushed in honey). But the peak of asthma technology was probably reached in the early 20th century when medicated cigarettes were introduced.
The entire history of inhaled medications is interesting and worth a read.
The Modern Era: MDIs
Fueled by the development of albuterol and Metered Dose Inhalers (MDIs), the asthma inhaler industry took off in the mid-20th century. Early on, albuterol was effectively propelled by CFCs.
Then in the 1980s, awareness of the depleted ozone layer led to MDIs being switched from CFCs to more ozone-friendly delivery gases such as HFA134a. Albuterol HFA is what most patients now use.
Unfortunately, the compound 1,1,1,2-tetrafluoroethane (HFA134a) is not great for the environment either. While it doesn’t ruin the ozone layer, all of those little HFA molecules are much more potent greenhouse agents than carbon dioxide. For this reason, yet another new format was invented, with albuterol available as a Dry Powder Inhalant (DPI). This is a very fine powder that is inhaled, and thanks to the delivery device, more medicine effectively reaches your lungs with a DPI than an HFA, without any greenhouse gases being used. Thus, a DPI is better for the environment and your lungs.
Still, in 2019, Albuterol HFA is more affordable and remains one of the most ubiquitous prescriptions in the world. With nearly 50,000,000 albuterol inhalers prescribed in the US each year, it is the 10th most frequently prescribed medication.
It is so common that we nearly take it for granted, but what is the carbon cost of these 50 million inhalers?
CO2e: Carbon Costs
For patients with intermittent mild asthma, it is reasonable to expect the inhaler to be used ~2x/week. With 90 doses in each HFA inhaler, that means a patient would need 1.15 inhalers per year. Accounting for priming sprays and an occasional extra dose, an estimated 1.25 inhalers/year costs 12.3kg of CO2 equivalent (CO2e) per year. That sounds pretty terrible, but how much CO2e does meat produce?
Giving up two 5oz steaks (or more likely one 10oz ribeye) just once each year will save nearly as much — 11.52kg of CO2e. In my opinion, giving up one steak per year does not a vegetarian make, so I reached out to the author of the original article, Alex Wilkinson, to clarify the claimed carbon savings.
Alex pointed out that while my numbers are correct for albuterol HFAs, his math also included the dual agent HFAs that also contain a steroid. These medications are usually prescribed for daily use, which would mean more utilization and more CO2e. Per his numbers, those inhalers cost 150–400 CO2e per year, although he admits that “real-world compliance with inhalers can be far lower, ” so the carbon impact may be much lower as well. In the end, switching a dual agent HFA to a DPI is the equivalent of giving up 5 ounces of steak per week. That is still not “giving up meat” as the authors state, but it is somewhat significant.
$$$: Financial Costs
If DPIs are better for your lungs and the environment than an HFA, then why do we still use HFAs? Cost. DPIs are newer and can cost more than twice as much. According to GoodRx.com, the cash price for albuterol in each form is:
Albuterol HFA: $23
Albuterol DPI (Respiclick): $57
Can you put a price on lowering your carbon footprint? Yes, if you use albuterol now you can: $34/inhaler, or about $40 per year.
If your asthma symptoms are more frequent, such that you should be using a dual agent inhaler daily, a DPI is actually cheaper than a HFA, with generic fluticasone/salmeterol costing only $51.
(Asthma tip: Even for mild intermittent asthma, GINA 2019 guidelines support using a dual agent fluticasone/salmeterol DPI for symptom management, off-label, in place of albuterol.)
Conclusion
Should patients switch from a HFA to a DPI inhaler? How much 1,1,1,2-tetrafluoroethane (HFA134a) do we really want to be inhaling, anyway? Is it better to pay more for a prescription if it decreases greenhouse emissions?
The answer will be different for each patient, but maybe it is time for prescribing habits to change. As a doctor, I now offer patients the option of upgrading to a DPI over a cheaper HFA.
