How The Montreal Protocol Changed Inhalers
Experts from various nations got together in Montreal during the 1980s. They studied the data and concluded that chlorofluorocarbons (CFC) were harmful to the ozone. They signed what became known as the "Montreal Protocol" in 1987.1 Since asthma inhalers used this CFC propellant, this would have an impact on asthmatics. Here’s what to know.
A little history
The history of asthma inhalers goes back to WWII. Along with fending off enemies, American soldiers in Europe also had to fend off against bugs. So, American entrepreneurs set off on a quest to invent bug spray. And they succeeded. They put the bug spray in pressurized cans. The propellant they used was CFC. This worked great. Bug sprays made it so soldiers could better focus on their jobs, as opposed to swatting at bugs.
So, the war ended. Entrepreneurs searched to find other uses for sprays. At this same time, there was a demand for a method of inhaling an asthma medicine called epinephrine. So, the medicine was placed in small pressurized canisters. Someone invented an actuator that allowed for a metered dose to be delivered. And, by 1957, the first inhaler entered the market. It was called the Medihaler Iso.
By the 1980s, there were various other asthma inhalers on the market. You had rescue medicine like Alupent and Albuterol. You had inhaled corticosteroids like Vanceril and Azmacort. The propellant used in all these inhalers was the same CFC propellant.
Then along came the environmentalists
It was learned that CFC helped deplete the ozone. Along with inhalers, there were a lot of items using the CFC propellant. These included anything from spray paints to bug sprays. So, various experts in this area met in Montreal, Canada, to organize a treaty to ban substances that have the potential to harm the ozone.
An agreement was reached and signed by 167 countries, including the U.S. It was termed the Montreal Protocol on Substances That Deplete the Ozone Layer. Usually, it’s simply referred to as the Montreal Protocol.2
Initially, asthma inhalers were given a pass.3-4 But, eventually, part of the agreement included phasing out using CFC propellants even for asthma inhalers. This was after a new propellant was invented. This new propellant was called hydrofluorocarbon (HFA).
A requirement was made by the FDA for pharmaceuticals to eradicate the use of the CFC propellant. Pharmaceuticals basically were left with three choices5-7:
- Switch to the new HFA propellant. This is what the makers of albuterol (Ventolin) did. CFC Ventolin was to be phased out by 2008. Now it’s called Albuterol HFA. Today they are Proair HFA, Proventil HFA, and Ventolin HFA. There is also a levalbuterol (Xopenex) HFA inhaler. The makers of beclomethasone (Vanceril) switched to an HFA inhaler now called Qvar.5-7
- Switch to a dry powder inhaler. This is what the makers of fluticasone (Flovent) did. They came up with the Diskus and introduced the purple Flovent Diskus.7
- Stop producing the inhaler. Working in coordination with the FDA, the following inhalers were set to be phased out. Nedocromil (Tilade), metaproterenol (Alupent), triamcinolone (Azmacort), and cromolyn (Intal) were set to be phased out by 2010. Flunisolide (Aerobid) and Primatene Mist were set to be phased out by 2011. An albuterol/ ipratropium combination inhaler (Combivent) and pirbuterol (Maxair) were set to be phased out by 2013.7-9
This was met with the ire of asthmatics who used these inhalers. Some asthmatics said the HFA inhalers didn’t work as well. But studies showed otherwise. In fact, they showed that HFA inhalers may work even better than CFC inhalers. Either way, we had no choice but to comply.
Looking back at this change
In my personal opinion, it has worked out rather nicely. That is, except for the cost of these new inhalers. That will be the subject of a future post.
But, as far as the inhalers using HFA propellants, they work just as well as they always have, if not better. Initial studies confirmed the new HFA inhalers worked equally well as the old CFC inhalers. They also showed HFA inhalers get 50% deeper into airways than the old CFC inhalers. So, that’s actually an unexpected bonus.
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