Lung inhaler accuracy

[poppysdad]

I’ve been taking various lung medicine inhalers for a number of years now. They all claim to give a precise metered dose of the contained medicine but on occasion I have my doubts. Sometimes I hardly detect any medicine was expelled when pressing the canister down and on others I sometimes detect considerably more than usual. So, just how accurate are these devices at expelling the correct amount of medicine.

 

Likewise when the canister is nearing getting empty, are you still getting the correct amount of medicine, I currently take 2 different ones and one claims 120 doses with recommended 4 doses per day so easy to work out how much should be left as obviously designed to be for  1 month. The other claims 200 doses but taken as and when needed so unless one religiously marks it down on each use it becomes very difficult to gauge when it should be replaced. I simply give it a good shake close to my ear to see if it sounds empty. Any suggestions on being more accurate. 

[mstevens]

I don't know which exact inhalers you're using but when I used Ventolin inhalers in the past and with the Symbicort inhaler I currently use, the inhaler seems much more effective for the first 60 - 70% of use. After that, it's almost like whatever is in the inhaler has become degraded and you may need two puffs instead of one.

 

The Symbicort inhaler I currently use has 120 doses and I need to use it just once a day, one puff in the morning and I am good until the next day. I have mild, well-controlled asthma. By the time the inhaler is showing around 35 or so doses left, I find it is much less effective. By the time it gets to 0 I need at least two puffs for it be to effective, even though there is clearly still some left in it.

 

These days I don't let it get that low. When it gets to around 20 or so remaining doses I bin it and get a new one.

Edited April 28, 2023 by mstevens