What is an important instruction for using a metered-dose inhaler (MDI)?

The instruction to exhale before using a metered-dose inhaler (MDI) is key to effective medication delivery. When a person exhales fully before taking a dose, it helps to maximize lung capacity and allows for the inhalation of the medication to be more efficient. This preparation ensures that the airways are clear for the incoming aerosolized medication, which can enhance drug deposition in the lungs.

In contrast, holding the inhaler upside down can prevent proper aerosolization and delivery of the medication. Using it only after exercise restricts its use to specific situations instead of as a necessary part of the asthma management plan. Holding your breath for 10 seconds after inhalation is often recommended, but it follows the inhalation rather than being a preparatory step. Instead, exhaling before using the inhaler is crucial for optimal inhalation technique and medication effectiveness.