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Metered Inhaler

A metered-dose inhaler is a pressurized container that releases a mist of medicine. Inhaled asthma medicines contain a gas that helps the medicine get into your lungs. Chlorofluorocarbon (CFC) depletes the ozone layer in our atmosphere. It has been replaced by hydrofluoroalkane (HFA). The medicine in HFA inhalers is the same as the medicine in CFC inhalers. It's the gas used to push the medicine out of the inhaler that is changing. The HFA inhaler looks just like a CFC inhaler, but is a little different. The spray comes out with less force, is warmer, and has a slightly different taste. It is not felt as much in the throat when inhaled, but you still get the right amount of medicine.

The valved holding chamber is a spacer that can be used with a metered-dose inhaler. The spacer helps you inhale more medicine into your lungs.

To attach the inhaler to the spacer:

  1. 1. Remove the caps from the spacer and metered-dose inhaler.
  2. 2. Shake the inhaler vigorously.
  3. 3. If the MDI has not been used before or if the MDI has not been used for a while, you must then "prime" the MDI. Do this by spraying several sprays of the medicine into the air. Each time you use the MDI, the next dose is drawn into a chamber inside the MDI. If the MDI has not been used or sits for a long time without being used, some of the medicine leaks out of the holding area. This means you will not get the full dose of medicine the next time it is used. Priming the MDI makes sure that you get the full dose of the medicine.
  4. 4. Insert the mouthpiece of the inhaler into the rubber-sealed end of the spacer.

To use the inhaler with the spacer:

  1. 1. Breathe all of the air out of your lungs. Then put the spacer into your mouth between your teeth. Make a tight seal around the mouthpiece with your lips.
  2. 2. Press the inhaler down once to release a spray of medicine. The medicine will be trapped in the spacer.
  3. 3. Breathe in slowly and deeply.
  4. 4. Hold your breath for 10 seconds. (This gives the medicine time to reach your airways.)
  5. 5. Take the spacer out of your mouth. Breathe out slowly.
  6. 6. Take a few normal breaths and then repeat these steps for another inhalation (puff) if required. Take the number of puffs prescribed by your health care provider.
  7. 7. If you are taking an inhaled steroid medicine, rinse your mouth and spit out the water after the last dose.

Cleaning the inhaler and spacer
Wash the spacer and the plastic case for the inhaler once a week with soapy tap water. Rinse and dry them thoroughly.

Replace the one-way valve or get a new spacer when the valve dries out and starts to curl.