There are some considerations that must be taken into account by those individuals who use inhalers regularly. The most important of these is determining when the inhaler is empty. Depending on the type and brand, inhalers can have between four and 200 doses, although the inhaler may still “puff” even after its medication has run out.

Patients should keep careful track of how often they use their inhalers so they know when to refill their prescription. This is easier to do with preventive medicine, which is used regularly. Simply divide the number of puffs in the container by the number of puffs each day. The result is the number of days the inhaler will last. For instance, if a medicine is to be used with two puffs, taken twice a day, then an inhaler with 200 doses should be replaced in 50 days.

This formula does not work as well with inhalers used to relieve symptoms of an asthma attack. One method is to keep track of the number of puffs on a calendar, and tally the number each month. Or, patients can purchase an add-on device for MDIs, which keeps track of the total number of puffs delivered by the inhaler.

It was once thought that placing a metered-dose inhaler in a container of water could indicate how much medication was left (depending on whether it floated or sank). However, that test is now not recommended and may even be dangerous as moisture can prevent the discharge of medication from the inhaler.

Inhalers should be cleaned every day. To clean the device, remove the metal cartridge (on those inhalers that have one) and rinse the applicator under running water. The hole in the mouthpiece, through which the medication is dispensed, should be washed particularly well.

After washing, the device should be air-dried. The protective cap for the inhaler should always remain on when the inhaler is not in use. The metal cartridge should be gently replaced once the applicator is completely dry.

In addition, patients should note the color of their inhalers. Inhalers used to prevent asthma symptoms, for instance, will be of a different color than an inhaler used to relieve an asthma attack. Often, a blue or white inhaler is used for rescue medication.

Individuals should contact their physician if they find that their inhaler is not working properly. Patients should also consult their physician if their symptoms are persisting.   In addition, patients who must use short-acting bronchodilators frequently (such as twice a week) to control asthma, should alert their health care provider. Their long-term treatment regimen may have to be altered. If breathing becomes difficult, an individual should always dial 911.