Asthma Inhalers


Until Jan 2009, asthma inhalers used Freon 12 as a propellant and worked well for asthma sufferers. As of January, inhaler manufacturers are no longer permitted to use Freon 12, and now use 134A. Unfortunately, the new inhaler does not provide relief from wheezing.

My question is, what is the difference between these two propellants (refrigerants)? Why won’t the 134A deliver the albuterol medication in the same way?


You are in the wrong place. It appears that HFC-134a is a longer molecule, and maybe that has something to do with it. It may also have to do with the pressure of the gas in the inhaler. HFC-134a is also slightly reactive, while CFC-12 is inert. Maybe there is a clue there, too. I suggest that you take this up with your pharmacist and doctor. They may have the information you seek already. If not, they need to know so that they can convey the information to the pharmaceutical company.


I do know you have to shake them up a lot longer than you used to, try shaking for 1 minute before inhailing. Wait 1 minute then shake for 30 more seconds then do 2nd


You said that I was in the wrong place, and later suggested that I speak to my pharmacist and physician. I came to Car Talk because I have already voiced my concerns with two pharmacists and three doctors. They all agree that they have had complaints from asthmatics, but the doctors do not agree that the inhaler does not work.

I was told twice by doctors that if the inhalers didn’t work, the FDA would remove them from the market. That means that I must trust my govt to test the effectiveness of the new inhalers.

My pharmacist told me a few days ago that I should write my congressman; that’s what she has been advising her asthmatic patients who complain about the new inhalers.

Before I wrote to the feds, I thought that I had better get a bit of input about what the difference is between the two propellants. Also, some opinions about why there is a difference in effectiveness would be helpful.

I had really hoped that there would be another asthmatic out there who reads these things, and would also have an understanding of chemistry.

Thanks for the input. I will continue to read the responses.


I wonder if Myth Busters has the technology to test the theory…’ Given that the medication is the same, Does it get chemically mixed differently within the two propellants resulting in a different medical dosage or strength ?’ And is there another propellant choice ?

Or is there an even more complex explanation as to what becomes of Albuterol when mixed with 1,1,1,2tetrafluoroethane ( r134a ) as opposed to dichlorodifluoromethane ( r12 ) ?

Although the propellants are automotive refrigerants ( hence your post in this forum ) the answer lies waaaaaay too deep in chemistry for us mere car guys.


You are right and wrong; I guess that is the best way to put it and I am sure you are not going to like it!
SO the previous inhalers were bad for the ozone. The studies with the newer ones have shown that some don’t get as much relief with them. The difference in them is the cold jet feeling rather than the medication delivery system. So it is a bit of placebo effect. In other words if you had the older propellant deliver water you would have still felt some relief and that is how our brains are wired. Your lungs will receive the medication even with the new system, provided you are using the correct technique. Sometimes if you change to a different brand it helps (ProAir ect). And sometimes this could be a sign that you need a step up in your asthma treatment altogether. This is esp true if you need your rescue inhaler more than ~ twice per week. Now see your specialist and remember this is not “medical” advice, rather “mechanical” advice.


What was the reason behind restricting the “Freon 12” inhalers? What agency (EPA,FDA,CIA,etc) came up with the restriction?


CFC-12 depletes the ozone layer and may not be manufactured or used anymore. That would be an EPA thing.


Are you sure it was the EPA. I know it sounds like it should be but the amount of problem gas from a inhaler is so small. I would like to read the administrative ruling. You would think some kind of exception is possible,you still can buy R-12 (well I bought some in 2004).


When you buy R-12 these days(for your car anyways), what you’re buying is old stockpiles of the stuff that were made before its manufacture was banned. As that stockpile dwindles, it has gotten progressively more expensive. (although I suspect that smuggling has maybe slowed it’s price increase somewhat)

I don’t know if there was previously an exception for inhalers or if they were also having to compete for the limited stockpile or what.


Hmm… that makes sense!


I am asthmatic, and have been using albuterol inhalers since somewhere around 1989. I have to tell you that I perceive absolutely no difference in the effectiveness of the new inhalers, as compared to the older ones that used a different propellant.

However, since my asthma is not severe, and since (thankfully) I use an inhaler only on an infrequent basis, I might not react the same way to these inhalers as someone with severe asthma might.


It’s sort of like accupuncture without the needles, and a lot of people get relief from asthma with it. Free download of manual. No, I am not connected with them. My son used it on rotations in med school, and find it works on most people for a variety of problems. Including vets sent home after 20 years in hospital with PTSD.


Perhaps you are no longer responding to the albuterol concentration…