Remove the cap from the MDI and shake well. Breathe out all the way. Place the mouthpiece of the inhaler between your teeth and seal your lips tightly around it. As you start to breathe in slowly, press down on the canister one time.

Do you shake inhalers?

Your inhaler has medicine to help your breathing and a “propellant” that helps push it into your lungs. You shake the canister to mix them so you get the right amount of each. If you don't, you might get too much of one and too little of the other.

Why do we need to shake MDI?

Instead, shaking determines the contents of the next dose, which fills the metering chamber as the canister recoils after actuation. If the pMDI is primed before use (see below), it should be shaken before each priming actuation to ensure that the metering chamber is filled with a homogeneous suspension of medication.