Getting the best out of your MDI

Using a spacer in conjunction with your metered dose inhaler (MDI) or asthma 'puffer' makes it easier to use the MDI and allows more of the asthma medicine to reach your lungs. Using a spacer leaves less medicine in the mouth and throat, reducing the risk of side effects such as throat irritation. Clinical trials have also shown that using a spacer with a reliever inhaler is as effective as using a nebuliser in an asthma attack.

Problems associated with using MDIs

Metered dose inhalers (MDIs) or puffers deliver an effective dose of asthma medicine into the airways, but perhaps as much as 85% can remain in the mouth and throat. Other problems with MDIs include: 

• sore throat (from the medication)
• hoarse voice (from the medication)
• need for good hand coordination to use the MDI properly
• ineffective technique can mean very little of the dosage is delivered to the lungs.

These problems can be reduced by the use of a spacer. To keep the risk of side effects to a minimum, it is still recommended to rinse your mouth (and spit out the water) after taking any inhaled preventer (corticosteroid) medication.

What are spacers?

Spacers are clear plastic devices with a mouthpiece or mask on one end and a hole for your inhaler at the other. A valve in the spacer mouthpiece opens as you breathe in and closes as you breathe out. A spacer makes your MDI easy to use and more effective for people of all ages. You can use your spacer with preventer, reliever, symptom controller and combination medicines.

Advantages of using a spacer

• Up to 70% more medicine reaches your lungs when you use a spacer 
• This may allow dose reduction
• A spacer used with a reliever inhaler is as effective as a nebuliser for acute asthma 
• There is less risk of throat irritation or a husky voice, as the spacer prevents medicine getting caught on the back of the throat or mouth 
• Many adults and children are unable to use their MDI effectively - the spacer reduces the need for perfect technique
  
• A spacer can help when you are short of breath and an inhaler by itself is difficult to use.

Cleaning a spacer

Priming: Wash your spacer before you use it for the first time. This is called 'priming'.

• Wash the spacer with warm water and dishwashing liquid
• Do not rinse
• Drip dry.

This method reduces the electrostatic charge so that the medicine does not stick to the spacer sides.

Regular cleaning: After priming, wash your spacer (as above) once per week (or more often if using Vicrom or Tilade).

Check spacer condition: Check the spacer for cracks. If used regularly your spacer may need to be replaced every 12-24 months.

How to use your spacer

• Shake the inhaler well (holding it upright)
• Fit the inhaler into the opening at the end of the spacer
• Seal lips firmly around the mouthpiece so there are no gaps (or place the mask so it seals around the nose and mouth) - most children should be able to use a spacer without a mask by the age of three years 
• Large volume spacers need to be tilted upwards at a 45 degree angle to ensure the valve works properly
• Press the inhaler once only
• Breathe in slowly and deeply through the spacer mouthpiece and hold your breath for 5-10 seconds
  OR take 2-6 normal breaths keeping the spacer in your mouth all of the time – you can breathe in and out with the spacer still in your mouth as most spacers have small vents to allow your breath to escape rather than going into the spacer
• Remove the spacer from your mouth
• Rinse mouth and spit out water or clean teeth after using a corticosteroid preventer
• If using a mask with preventer medication wash the child’s face after use
• If you need more than one dose of medication wait one minute and then repeat these steps for further doses, making sure that you shake your inhaler between doses.

Where do I get a spacer?

Ask your doctor or local medical centre about obtaining a spacer for use with your asthma medicine.

Related topics

Also see: Puffers and other devices and Peak flow meters 

Original material provided by The Asthma Foundation of New Zealand, 2010. Reviewed by everybody, November 2010.