What you should know about inhaled corticosteroids

Facts | 27/09/2023
What you should know about inhaled corticosteroids
Are you concerned about taking corticosteroids to control your asthma? We looked at some common questions when it comes to preventer inhalers.

For some 40 years, inhaled corticosteroids, ICSs, have been the frontline treatment for anyone with persistent asthma. Effective at improving lung function, preventing and controlling symptoms, reducing the risk of flare-ups and minimising the impact of asthma on our everyday lives, inhalers containing corticosteroids make a world of difference to our lungs and lives. 

Despite this, studies show that most people with asthma aren’t using their preventer medication as they should do. We looked at some preconceptions that might be holding them back. Here are answers to some of the most common questions about inhaled corticosteroids. 

Is it safe to use inhaled corticosteroids? 

Unlike oral steroids, a preventer inhaler sends corticosteroids – anti-inflammatory medication – straight to your lungs, minimising absorption into the rest of the body. If used properly and prescribed in standard doses, treatment is safe and unwanted side effects are few. Some people can develop oral thrush and hoarseness, but these can be controlled by rinsing the mouth after using the inhaler. It’s important to always read carefully the package leaflet that comes with your inhaler and follow your doctor’s instructions. If you experience any side effects, please consult your doctor. 

Inhaled corticosteroids are some of the most closely studied drugs in clinical use. They show that inhaled corticosteroids are effective in the treatment of asthma and the side effects are rare and can be minimised by using a low or moderate dose of ICS. 

Can I stop using my preventer inhaler when my symptoms disappear? 

It should be noted that using inhaled corticosteroids does not provide short-term relief. The positive effect will come in the long term, and it may take days, weeks or even months to see a difference in your asthma control. Knowing this, it may be easier to understand that if you have asthma, you should not stop taking your long-term control medication even when you feel well. 

Asthma is a chronic disease, and it doesn’t simply disappear. Some children experience a cure from asthma, but for some of them asthma will reappear later in life. As an adult, you may have long stretches when you are symptom-free. In that case, your doctor may prescribe a lower dose ICS to ensure it stays that way. A decision to change your medication should be made only together with your healthcare provider.  

Could I simply use a reliever inhaler for flare-ups? 

If you have persistent asthma, the best way to stay on top of symptoms is to use your preventer inhaler consistently and keep your reliever inhaler on hand in the event of a flare-up.  

A reliever is a short-acting bronchodilator which gives quick relief to shortness of breath. It is important that the reliever is not used alone in the treatment of asthma. If you’re using your reliever inhaler several times a week, you’re probably tolerating symptoms unnecessarily. Using inhaled corticosteroid treatment even when you feel fine means you’re keeping inflammation at bay.  

It is also possible that you will be prescribed inhaled corticosteroids in combination with long-acting bronchodilators. The combination is used in both controlling asthma and relieving symptoms. 

In 2015, a comprehensive scientific review found 24 percent of exacerbations and 60 percent of asthma-related hospitalisations were due to people not sticking to their treatment plan. Correct inhaler technique is also of the utmost importance for good asthma control. 

Can inhaled corticosteroids increase my weight? 

It is possible that oral corticosteroids increase weight, especially in high doses. However, no weight gain has been reported with inhaled steroids.  

To the contrary, with good asthma control engaging in exercise may be easier and more rewarding and hence it may help to maintain a healthy weight. For some asthmatics the fear of flare-ups has prevented them from exercising.  

As with any medically manageable condition, finding the ideal control regime for asthma is individual. If you have concerns, your best option is always to talk to your doctor. 



  1. Berthon BS et al. A systematic review of the effect of oral glucocorticoids on energy intake, appetite, and body weight in humans. Nutr Res. 2014;34(3):179-90.  
  2. Boslev Bårnes C et al. Asthma and Adherence to Inhaled Corticosteroids: Current Status and Future Perspectives, Respiratory Care 2015; 60(3):455-68. http://rc.rcjournal.com/content/60/3/455 
  3. Cordova-Rivera L et al. A Systematic Review of Associations of Physical Activity and Sedentary Time with Asthma Outcomes, J Allergy Clin Immunol Pract. 2018;6(6):1968-81. https://www.jaci-inpractice.org/article/S2213-2198(18)30127-2/fulltext  
  4. Barnes PJ. Inhaled Corticosteroids, Pharmaceuticals 2010;3(3):514-40. https://www.mdpi.com/1424-8247/3/3/514/htm 
  5. Lavorini F et al. Correct inhalation technique is critical in achieving good asthma control, Prim Care Respir J. 2013;22(4):385-6. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6442870  
  6. Rank MA et al. The risk of asthma exacerbation after stopping low-dose inhaled corticosteroids; A systematic review and meta-analysis of randomized controlled trials, J Allergy Clin Immunol 2013;131(3):724-29.e2. https://www.jacionline.org/article/S0091-6749(12)01924-0/fulltext  
  7. Shang W et al. The safety of long-term use of inhaled corticosteroids in patients with asthma: A systematic review and meta-analysis. Clin Immunol. 2022;236:108960. https://pubmed.ncbi.nlm.nih.gov/35218965/  


Date of preparation: September 2023 / EASYH-3443


If you get any side effects, talk to your doctor, pharmacist or nurse. This includes any possible side effects not listed in the package leaflet. You can also report side effects directly via the Health Products Regulatory Authority (HPRA) website: www.hpra.ie or email medsafety@hpra.ie


You might be interested in these:


Orion Corporation is a globally operating Finnish pharmaceutical company. We develop, manufacture and market human and veterinary pharmaceuticals and active pharmaceutical ingredients. The dry powder inhaler developed at Orion is in the core of our respiratory therapy area.