A spacer holds the spray before the spray is breathed in. Using a spacer with a puffer allows more medicine to get to where it is needed in the breathing tubes or airways. A puffer and spacer when used correctly can increase the amount of medicine that reaches your lungs by up to threefold.
A puffer and spacer prevent throat irritation by reducing the amount of medicine sitting in your mouth or throat. Spacers have a one way valve that stops air being breathed into the spacer while the spacer is in your mouth.
If used correctly, a puffer used with a spacer is at least as effective as a nebuliser in delivering a similar dose of medicine, that is, 4 to 10 puffs equals one nebuliser dose.
If you change the spacer you are using, particularly for your preventer or combination medicines, the amount of medicine you receive may be different, so check with your doctor if your symptoms change.