Spacer

Spacers or inhalation aids are used as part of inhalation therapy with metered dose inhalers for respiratory diseases such as asthma and COPD. They are placed upstream of the dosing aerosol and absorb the pressure of the spray in their chamber. Spacers reduce side effects of the drugs and optimise their therapeutic effect.

Metered dose inhalers are the most common and successful therapeutic use for asthma and COPD worldwide. They atomize liquid drug solutions into tiny aerosol particles that are directly inhaled into the respiratory tract. However, cortisone sprays in particular cause a number of side effects such as fungal infections in the mouth, irritation of the throat and hoarseness. The cause of these side effects of inhalation therapy is the high exit speed of the aerosol when a spray is triggered. Parts of the medication get stuck on the palate and in the throat.

Spacers have 3 advantages for the patient:

• When inhaled through the chamber of the inhalation aid, the airflow transports the particles more evenly and deeper into the airways. This allows more active substance to be deposited in the lungs.
• When inhaling via the inhalation chamber, less drug remains in the mouth and throat area, side effects are minimized.
• The aerosol can be exhaled by the patient from the chamber of the inhalation device at a staggered time, i.e. spray and inhalation do not have to be coordinated at the same time.

1. Global Initiative for Asthma (GINA):Global strategy for asthma management and prevention. www.ginasthma.org, update 2019