Side effects related to inhaler use are usually minor. Patients may develop tongue or throat irritation as the result of the powder passing through the mouth and throat. The powder may also leave an unpleasant taste in the patient’s mouth. In addition, swallowing any medication that remains in the mouth after inhaler use can lead to minor stomach upset and heartburn.

More serious side effects associated with the use of inhalers include:

• Thrush mouth. Usually caused by inhaled corticosteroids, this condition is a yeast infection that occurs at the back of the throat. Symptoms include a white film that covers the back of the throat and the tonsils. An antifungal mouthwash is often used to treat this condition.
  
  
• Asthma exacerbations. While metered-dose inhalers are very commonly used to treat asthma, the CFCs (chlorofluorocarbons) that discharge the medication in metered-dose inhalers will occasionally exacerbate an individual’s asthma. In these cases, a physician can recommend a dry powder inhaler that does not use CFCs. Because of the danger CFCs pose to the ozone layer, they generally are being phased out in most countries. An ozone-friendly propellant is replacing CFCs. Known as HFAs (hydrofluoroalkanes), this propellant has a different taste but the effectiveness of the inhaler remains the same.

Patients can lower their risk for side effects by thoroughly rinsing their mouth after using an inhaler and using their inhaler exactly as prescribed by their physician.