Tips for Using Metered-Dose Inhalers

Metered-dose inhalers (MDIs) are some of the most prescribed asthma inhalers today. Here are a few tips that will help you get the most out of your MDI.

There are now many different types of inhalers for asthma such as dry powder inhalers and breath-actuated inhalers. Make sure that the instructions you are following are for your type of inhaler.

Because your asthma control is dependent on getting medication into your lungs, your inhaler technique is very important. While your healthcare provider is one source of education for inhaler technique, there are other options. Your pharmacy might be able to give you instructions. You might also ask your healthcare provider about referring you to an asthma educator who can review your technique and provide feedback.


Practice, Practice, Practice!

Woman using a bronchodilator, France

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One thing that should help you master the technique of using a metered-dose inhaler is to watch yourself follow the steps in front of a mirror.

You can also ask your healthcare provider, respiratory therapist, or office nurse to watch you use your MDI. Do not practice with a real prescribed medicine because you could inadvertently exceed your prescribed daily dose and experience adverse side effects. Ask your healthcare provider for an MDI that does not contain active medication. This “placebo” MDI can be safely used to practice MDI technique.


Prime New or Infrequently Used Inhalers

If your metered-dose inhaler is brand new, or if you haven’t used it ​for a while, you may need to “prime” it before use. The specific instructions vary, and the length of time since the last use may be a few days or a few weeks.

In general, you’ll need to shake the MDI, then hold it away from your mouth and spray it one or more times into the open air. You may need to shake the inhaler before each spray. Familiarize yourself with the directions that came with your inhaler.

Priming will help make sure you get the full dose once you get ready to use the inhaler.


Don't Skip the Exhale Step

An important step in using your MDI is to blow out all the air in your lungs that you can before you breathe in the puff of medicine. Exhaling not only helps you take a deeper breath, but it also helps you get the medicine deeper into your airways.


Wait 1 Whole Minute Before a Second Puff

If two puffs are prescribed at a time for either your controller medicine or your rescue inhaler, be sure to wait a full minute after the first puff before you take the second puff. This will ensure that the first puff has been fully circulated throughout your airways.


Prevent Fungal Growth

If you use an inhaled steroid medicine in your MDI, you could have some fungal growth in your mouth from leftover medicine after your puffs. To prevent this, rinse your mouth well with water after each dose. Spit out the water; don’t swallow it. Also, using your MDI just before brushing your teeth is a good way to avoid three things: fungal colonization, a bad taste in your mouth, and a hoarse voice.


Watch the Heat

Never store your MDI in a place where it may be subject to high temperatures. This includes car trunks and glove boxes, or anywhere in the direct sunlight. Kitchens and bathrooms are better avoided, as well.


Know the Difference Between an MDI and a DPI

Metered-dose inhalers are not the same as dry powder inhalers (DPIs), and using them is different, too. Make sure you know what you have. Examples of DPIs are:

You don’t need to shake a DPI and you should never blow into the inhaler.


Take Good Care of Your Inhaler

It’s important to keep your asthma inhaler clean so that it will keep working properly. When it’s not kept clean, it may clog, preventing you from getting the full dose of your medicine in a puff.

For many inhalers, you should rinse the actuator (but not the canister that contains the medication) under warm, running water for at least 30 seconds, at least once a week. Let it air dry.

Note that some other inhalers should not be cleaned with water, so be sure to follow the directions that came with your inhaler.

1 Source
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  1. National Heart, Lung, and Blood Institute. How to use a metered-dose inhaler.

By Pat Bass, MD
Dr. Bass is a board-certified internist, pediatrician, and a Fellow of the American Academy of Pediatrics and the American College of Physicians.