Thrush From Inhaled Steroids

A Fungal Infection From Asthma Steroid Inhalers

Inhaled Steroids
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The use of inhaled steroids for the treatment of asthma can sometimes increase the risk of developing thrush—a fungal infection that is diagnosed by a doctor scraping off white, soft patches on the tongue and/or mouth and looking at them under a microscope. 

What is Thrush?

A type of fungus called Candida yeast lives normally in small amounts within the mouth. But with the use of certain medications (like chemotherapy or steroids) or when a person develops a weakened immune system (like from diabetes or HIV/AIDS), the yeast can start growing rapidly and visibly within the mouth.

This overgrowth of yeast in the mouth is called thrush, also referred to as oral candidiasis.

Thrush appears as white patches often on a red base within the mouth or on the sides of the tongue. It can be painful, often described as sore or burning. Some people with thrush also describe difficulty swallowing (which may indicate that thrush is also present in the esophagus) and/or notice cracking at the sides of their lips—this condition is called angular cheilitis.

Who is More Likely to Develop Thrush?

Since corticosteroids weaken a person's immune system, inhaled steroids used to manage lung conditions like asthma can trigger thrush. People with more severe asthma are generally more prone to developing thrush because they tend to use higher dosages of inhaled steroids. Oral steroids too can predispose to the development of thrush, and oral steroids are more commonly used in people with severe asthma.

How is Thrush Prevented and Treated?

Thrush can normally be prevented with mouth rinsing and tooth brushing after the use of inhaled steroids. That being said, some people still tend to get thrush despite following these measures. 

Once thrush has developed, a person may need treatment with nystatin mouthwash or oral Diflucan (fluconazole).

Some people require periodic rinsing (once daily to a few times per week) with nystatin in order to keep thrush from coming back.

The use of a spacer device with a steroid metered dose inhaler can be helpful in reducing or preventing thrush. This device acts to reduce the amount of medication delivered to the mouth and helps more medication get to the lungs, where it’s needed most. Unfortunately, many new inhaled steroids utilize dry powder inhalers (such as Advair, Pulmicort, and Asmanex) that don’t utilize a spacer.

Dry powder inhalers seem to especially predispose people to getting thrush. The powder from these inhalers doesn’t dissolve well in water, so some people find that rinsing their mouths and brushing their teeth doesn’t help to keep the thrush away. For these people, rinsing with an alcohol-based mouthwash, such as Listerine, may be more helpful in preventing thrush.

A Word From Verywell

Like all medications, inhaled steroids for asthma control pose some risks, like the development of thrush. That being said, inhaled steroids are considered the most potent and consistently effective long-term control medication for asthma, according to the Expert Panel guidelines from the National Heart, Lung, and Blood Institute.

With that, in order to best manage your asthma, it is important to follow the instructions of your doctor and take your inhaler as prescribed. Remain proactive in your asthma health and address any worries or concerns with your healthcare provider.


Centers for Disease Control and Prevention. (2014). Oropharyngeal/Esophageal Candidiasis ("Thrush").

Godara N, Godara R, Khullar M. Impact of inhalation therapy on oral healthLung India. 2011 Oct-Dec;28(4):272-75.

National Heart, Lung, and Blood Institute. (2010). Guidelines for the Diagnosis and Management of Asthma. 

Schleimer RP, Spahn JD, Covar R, Szefler SJ. Glucocorticoids. In: Adkinson NF, Yunginger JW, Busse WW, et al, eds. Middleton’s Allergy Principles and Practice. 6th edition. Philadelphia: Mosby Publishing; 2003:870-914.

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