What is the first step in using a Meter Dose Inhaler (MDI)?

The first step in using a Meter Dose Inhaler (MDI) is to exhale completely. This step is crucial because it helps to ensure that the lungs are empty and can take in a full dose of the medication when the inhaler is used. By fully exhaling, the individual maximizes the inhalation capacity and allows for better absorption of the medication into the airways.

While shaking the MDI and attaching it to a spacer can be important steps in the process, they should follow the exhalation phase. Shaking the inhaler ensures that the medication is mixed properly within the canister for effective delivery. However, it is vital to be in the right position with completely exhaled air to allow for optimal inhalation of the medication afterward. Thus, starting with a complete exhale is foundational for the proper use of an MDI.