Some inhalers have a dose counter, this will tell you how many puffs are left in your inhaler.
If you have a metered dose inhaler, it can be difficult to know when your inhaler is empty. Even if the inhaler is empty it will still “puff” when you spray it or sound like it has something in it when you shake it. This is because there is a propellant in the inhaler to make sure the medicine reaches your lungs.
If your inhaler is without a counter, you can also keep a tally of the puffs your child has taken.
In the case of a controller inhaler you can work out when the inhaler is likely to run out, for example a 200 dose inhaler used 2 puffs twice daily may last approximately 7 weeks.