How to Determine when an Inhaler is Empty
Currently, not all asthma inhalers allow to easily determine the number of doses (or "puffs" for MDIs) of remaining medication. Newer models tend to include a numeric counter that displays the amount of doses that can still be applied. Ventolin-HFA, Flovent-HFA, Proventil, Advair Discus are some of the best examples. Regrettably, only a few brands on the market include such feature; most inhalers have no additional functions to help determine if they are empty. Nevertheless, it is still possible to know if you need to buy asthma inhaler to restock, or if you can keep using the one you have.
Calculate your Asthma Inhaler Medication Amount
The approach in this method is very simple - check the maximum dose capacity of your asthma inhaler and keep track of the amount of puffs you use per day. Most MDIs have a predetermined amount of doses that can be applied, ranging from 70 to 200, depending on the brand and type of medication being used. The easiest way is to refer to the instructions provided with your asthma inhaler and figure out this maximum amount. You can ask your doctor or pharmacist about the maximum amount of doses in a given brand if you are not sure.
If you want to figure out the remaining number of puffs for an inhaler you use regularly, let's say twice per day, simply divide the maximum number of puffs by 2 (the number of daily doses). Since most inhalers have 200 doses, 200/2=100 days, or 3 months+1 week. Write down the date on which your asthma inhaler should get empty, and get a new one at least 1 week prior.
For "reliever" inhalers, the situation is a little more complex, since they are not used a fixed amount of times per day. If you want to know exactly how many times your inhaler can still be used, one of the best ways is to write down the amount of puffs you use each day. Then, simply subtract this number from the remaining amount available for your inhaler.
Should you buy inhalers online and find it difficult to determine the maximum number of puffs, below are some of the common amounts of doses available for asthma inhalers:
- 60 - Advair discus;
- 100 - Aerobid, QVAR;
- 112 - Intal (8.1 g);
- 120 - Serevent, Flovent HFA;
- 200 - Flovent, Combivent, Atrovent, Ventolin, Proventil, Alupent, Metaprel, Intal (14.2 g), Pulmicort;
- 240 - Azmacort;
- 300 - Max air;
- 400 - Max air autohaler.