Inhaled corticosteroids are used for long-term management of asthma symptoms. This means they are used daily and for several years. Their prolonged use leads to many side-effects, especially if the corticosteroids are used in high doses: Soreness in mouth and throat, Hoarseness of voice, thrush infection in the mouth, temporary delay in growth, reduced thickness of bone, clouded eye lens, huge pressure of blood or fluid in the eye and glaucoma.

These side effects can be minimized or prevented by:

1. Using a spacer. The spacer is a chamber that can be connected to a metered-dose inhaler. Since the spacer has just one valve, the corticosteroids can be kept in the spacer before inhalation. So, the user can inhale the whole medicine in many breaths. In addition, the use of a spacer prevents candidiasis (thrush in the mouth), prevents dysphonia (hoarse sounding voice), reduces volume of corticosteroids reaching bones and other body organs.

2. Washing mouth with water after taking corticosteroids. This water must be spat out since the corticosteroids would be absorbed in the blood if the water is swallowed.

3. Taking low doses of corticosteroids. The doses can be lowered if other asthma medications, such as a sustained-release theophylline, a long-acting inhaled beta2-agonist and a leukotriene pathway modifier, are also used.