Many people who take medication to treat or manage their lung condition may be advised to take corticosteroids, usually known as ‘steroid’ therapy.

This page explains the different types of steroid therapy and the effects that the steroids might have on you.

Steroids will be prescribed at an appropriate dose to control your symptoms. How effective they are depends on the lung condition and will vary from person to person.

The effectiveness of the therapy will be measured by changes in your lung function, as well as your ability to exercise, relief of your symptoms and the effect of the steroids on your day-to-day life.

Steroids may be used to treat a number of different lung conditions and can be prescribed in different forms, including via an inhaler or as a medicine that you swallow (oral steroids).
They may be prescribed short-term, for example in emergencies, or long-term to ease symptoms or to stop your condition getting worse.

Sarcoidosis and some types of pulmonary fibrosis may not respond to inhaled steroids but may benefit from oral treatment. Conditions such as asthma and chronic obstructive pulmonary disease (COPD) respond to both methods. COPD is an umbrella term covering chronic bronchitis and emphysema.

In general, conditions that cause inflammation, such as asthma, respond well to steroids, while conditions that cause lung damage or scarring, such as COPD or pulmonary fibrosis, respond less well.

Steroids are also used following a lung transplant to reduce the risk of the body rejecting the new lungs.

How are steroids prescribed and taken?

Inhaled steroids

Inhaled steroid therapy allows the drug to be delivered directly to the lungs and upper respiratory system. Because of this, smaller doses can be used, reducing the risk of side-effects in the rest of the body. This method is used to treat a variety of lung conditions, including asthma and COPD.

In asthma, inhaled steroids reduce inflammation, which prevents symptoms and reduces attacks. Inhaled steroid treatment can be used to reduce the number of lung attacks (a flare-up or exacerbation of symptoms) in people with COPD, though it will not prevent the disease from getting worse.
Inhaled steroid therapy allows the drug particles to act directly on the inflamed cells and help reduce swelling and reduce mucus.

For the best results, inhaled steroids should be used regularly as prescribed by your doctor. In asthma, the benefits are usually felt three to seven days from the start of treatment, but the improvement may continue over many weeks. You should be assessed on a regular basis to ensure that the use of steroids is effective.

For asthma, inhaled steroids are the first form of prevention treatment used, though if any symptoms remain, additional treatments may be prescribed by your doctor.

For COPD, inhaled steroids are also taken with drugs called ‘long-acting bronchodilators’ to treat people with more severe disease, especially those who have frequent lung attacks.

If your lung condition could benefit from taking both inhaled steroids and long-acting bronchodilators, then a combined steroid and long-acting medication is simpler and may also make both drugs more effective.

Some people also find it more convenient to take two drugs in one inhaler.

A variety of types of inhaler can be used to deliver the steroids to the airways. It is very important for both safe and effective use of the drug that you use the device correctly and with the right technique. This technique should be explained by your doctor, nurse or pharmacist.

Oral steroids

Oral steroid therapy means taking the drug in tablet form. You may be prescribed a short or long-term course of oral steroids and you should always take the steroids according to the instructions given when they are prescribed.

Short-term use of steroids

In the short-term, oral steroids are important to treat an attack of asthma or COPD. In this situation, your doctor may tell you to take the tablets for between one and three weeks.

If you have frequent asthma or COPD attacks, ask your doctor or health care professional about the benefits of having a standby course of steroids on hand that you can take at the early signs of an attack.

If you have COPD, lung attacks are often due to a chest infection, so oral steroid therapy may be combined with antibiotics.


Long-term oral steroid therapy may be prescribed if your lung condition is particularly severe and the treatment cannot be stopped without your symptoms coming back. This is called a ‘maintenance dose’. The dose should be kept as low as possible.

If your health care professional thinks this is the best treatment for you, they will discuss with you the likely benefits and any side-effects or disadvantages of the treatment.

Should I be worried about taking steroids?

Many people are worried about taking steroids, but studies show that inhaled steroids are safe when taken in moderate or low doses, though side-effects may occur with high doses used long-term. Oral steroids are safe – and vital in emergency situations – but can have side-effects if a long-term maintenance dose is taken.

What are the side-effects?

When you are prescribed steroid therapy your health care professional should explain the benefits, and also tell you about likely side-effects or risks involved. You should also always read the information that comes with your medication.

Side-effects of inhaled steroids include:

  • Changes in your voice. Your voice may become hoarse, due to inhaled drug particles affecting the vocal cords as muscles are weakened.
  • Oral thrush. This may appear as white coated patches on the tongue or reddened patches, which can be very sore. Using a ‘spacer’ (a plastic device with a mouthpiece) with the inhaler may help. Rinsing your mouth after use and use of oral anti-fungal medication may also help. Some people also report that small amounts of fresh pineapple juice are effective.
  • If you are taking a high dose, you may notice that you bruise more easily, or that your skin becomes thin or fragile.

Side-effects of short-term oral steroids include:

  • Changes to your sleep pattern and possible sleepiness.
  • Changes to your mood.
  • Indigestion.

Side-effects of long-term or frequent short-term courses of oral steroids include:

  • Weight gain. This is because steroids can cause fluid retention and will increase your appetite and make it harder to metabolise fat. It is therefore important to eat a healthy and balanced diet.
  • Diabetes. Steroids can increase the blood sugar so can make diabetes harder to control.
  • Steroids are one cause of the eye condition cataracts.
  • Steroids can cause thinning of the bones (called osteoporosis) and people on long-term steroids may be given treatment to help prevent this happening.
  • Bruising and thin or fragile skin.
  • Indigestion and stomach ulcers. You may need to take a treatment to reduce acid and protect your stomach.
  • Changes to your mood.

You may also become more vulnerable to certain infections when taking steroids. For example, people with COPD on high doses of inhaled steroids are slightly more prone to the chest infection pneumonia.

Side-effects will vary from person to person and any concerns that you have should always be discussed with a health care professional. This will help you get the best from your medication and so help keep you up to date with the management of your condition.

When long-term oral or very high dose inhaled steroids have been prescribed you should also be given a steroid card to carry, which records how much of the steroid you are taking, in case of emergency or illness.

When you are taking your prescribed steroids your body will reduce or stop making its own natural steroid.

If you have been taking oral, or very high dose inhaled steroids for a sustained period of time (more than three weeks), your doctor will advise you to reduce your dose slowly so that your body can gradually start making its own steroid again.

A rapid reduction in your medication may result in tiredness, nausea, weight loss and an upset stomach.

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Code: FL25 

Last medically reviewed: September 2011

For references call 020 7688 6510