Steroid inhalers are preventers. They reduce inflammation in the airways over time rather than relieving symptoms immediately, which is why they are taken every day even when you feel well.

An important reassurance: inhaled steroids are not the same as steroid tablets. The dose is far smaller and delivered to the airways rather than throughout the body, so the effects associated with tablets such as prednisone largely do not apply. Most inhaler side effects are local, in the mouth and throat, and are preventable.

Common side effects during long-term use

These are largely preventable, and the two measures that prevent them are worth doing properly:

If thrush or hoarseness keeps recurring despite this, ask for your technique to be checked. Poor inhaler technique is common and is usually the explanation.

Serious or persistent symptoms to discuss with a clinician

Get emergency help if breathing worsens rather than improves immediately after using an inhaler, or if you cannot speak in full sentences, your lips look blue or grey, or your reliever is not working.

At higher doses over long periods, some steroid can be absorbed into the body. This is uncommon at usual doses but is why high-dose treatment is reviewed rather than left indefinitely. Considerations include effects on bone density over years, growth monitoring in children, and rarely adrenal suppression. Report unusual tiredness, dizziness or weight loss on long-term high-dose treatment.

Children on inhaled steroids should have their growth monitored. This is routine rather than a sign of concern, and untreated asthma also affects growth.

Dose changes, missed doses and monitoring tests

Do not stop your preventer because you feel well. Feeling well is usually evidence it is working. Stopping allows inflammation to return over days to weeks, and the deterioration is often not noticed until symptoms are back.

Equally, needing your reliever more often than usual is a signal the preventer is not doing enough, and needs review rather than simply more reliever. See Ventolin side effects.

Ask for a written asthma action plan, an annual review, and an inhaler technique check at each review.

Interactions with OTC medicines and supplements

What to ask your doctor before changing treatment

Related chronic medication guides

Medical Disclaimer: This content is for informational and educational purposes only and does not constitute medical diagnosis, prescription, or professional advice. Always read the patient information leaflet and consult a qualified doctor or pharmacist regarding any medicine or health concern.