Taking steroid tablets for severe asthma

How they can help your asthma and possible risks and side effects

Find out how steroid tablets can help your asthma, what the risks and side effects are, and when you should ask for a referral to a specialist asthma clinic.

How steroid tablets can help your asthma

Steroid tablets (usually prednisolone) stop inflammation in your airways getting worse, reduce your asthma symptoms, and lower your risk of having a life-threatening asthma attack.

If you’re struggling to control your symptoms, or you’ve had an asthma attack, it’s important to treat the inflammation in your airways with steroids. If the inflammation is left untreated, you’re more at risk of symptoms continuing to get worse or more asthma attacks.

Even if you’ve been prescribed steroid tablets, you’ll still need to take all the other medicines you’ve been prescribed and continue using your preventer inhaler.

Did you know? The steroids used in steroid tablets to treat asthma are called corticosteroids. These are a copy of steroids the body produces naturally, to deal with injury or inflammation. They are not the same as the steroids bodybuilders use.

When you’re likely to need steroid tablets

You’re most likely to be prescribed oral steroids if you have a flare up of your symptoms or an asthma attack. This should be a short course to deal with symptoms, and once you’ve finished the course your doctor will advise you how to safely stop taking them.

However, sometimes steroid tablets are prescribed long term. This is more likely if:

  • your asthma is not controlled with the maximum doses of a preventer inhaler and other add-on treatments
  • you’re waiting to be considered for alternative severe asthma treatments
  • your symptoms get worse each time you come off a short course of steroid tablets.

How long do I need to take steroid tablets for?

This depends on why you’ve been prescribed them.

Short courses of steroid tablets

You may need a one off, short course to help you treat an asthma attack. This is important for your recovery, and unlikely to cause harmful side effects.

However, if you need two or more short courses in a year, or your symptoms come back once you’ve finished the course, you should ask your GP for a referral to a specialist clinic because this is a sign that your asthma is difficult to control.

Taking steroid tablets long term

You may need a longer course, or to take steroid tablets continuously if your symptoms are not well controlled despite other treatments, or while you are waiting for alternative treatments, such as biologic treatments.

Some people may need to continue taking them if they are not eligible for biologic treatments.

If you’re taking steroid tablets continuously you should be under the care of a respiratory specialist.

Remember to always carry a steroid card. A steroid care card lets healthcare professionals know you take steroid medicines.

Risks and side effects of steroid tablets

Steroid tablets can be lifesaving, but as our severe asthma report shows, they can have side effects, particularly if you’re taking higher doses over a long period of time.

It might be reassuring to know that your doctor will always aim to prescribe the lowest steroid dose for good control to minimise any side effects.

Most of these side effects are unlikely with a short course of steroids, but they may happen if you keep needing short courses to deal with symptoms that keep coming back, or because you keep having asthma attacks.

  • Some side effects may be noticeable straight away, such as stomach problems, or changes to your mood (feeling depressed, or feeling ‘high’ or manic).
  • Others may only be noticeable after weeks or months, such as weight gain, or a puffy ‘moon’ face. These are unlikely with a short course of steroids but can happen with repeated courses.
  • Some side effects may develop over time. You’re more at risk of side effects like steroid-induced diabetes, or osteoporosis or thin skin and bruising if you’ve been taking steroid tablets for a long period of time, or if you need several short courses of high dose steroids in a year.

In our severe asthma survey in 2020, 93% said they had at least one condition linked to taking oral corticosteroids long-term. Read more in our special severe asthma report Do No Harm.

See the patient information leaflet for a full list of side effects, and always talk to your doctor or pharmacist about other medicines you’re taking.

If you get any side effects, including any not listed here, or in the patient information leaflet, talk to your doctor, pharmacist or nurse. You can also report side effects through the Yellow Card Scheme.

Weight gain

In our 2020 survey of 3000 people who had taken steroid tablets in the last year, 43% said they had put on weight after being on long term steroid tablets.

This is because steroids can increase your appetite. They can also cause fluid retention and bloating. Prednisolone can also make your body store fat in other places around the body, like the face or abdomen.

If you’re not able to keep fit and active because of your asthma symptoms, lack of physical activity can add to the problem.

This side effect doesn’t just affect people on long term steroids. Anyone on four or more short courses of steroids in a year is also at higher risk of weight gain.

Talk to your doctor if you want advice on how to maintain a healthy weight. For some people their weight drops back to something more normal for them once they stop taking steroids. But for others find it hard to shift the weight, even after they’ve come off steroids. Your doctor may be able to help the water retention, and offer advice about ways to watch your calories. Try to aim for a healthy, balanced diet.

Difficulty sleeping

In our survey, 40% said they found it difficult to sleep well when taking steroids, often due to racing thoughts.

If you take your daily steroid tablet in the morning, it means that your body has time to process it before bedtime.

Mood changes

Taking steroid tablets can affect your mood. You may notice this side effect soon after you start taking steroids.

You may feel manic, full of energy, or hyped up and unable to sleep well.
You may also feel very low, or anxious and depressed.

This is quite a common side effect, affecting about 5 in every 100 people taking prednisolone.

Before taking a course of steroid tablets, let your doctor or pharmacist know if you have ever had severe depression, or manic depression (bipolar disorder), or if there’s a history of severe or manic depression in your family.

Weak bones and fractures

The risk of thinning bones and breaks is much higher if you take high dose steroids for more than three months.

Your doctor may suggest a bone mineral density scan known as a DEXA scan to assess your risk. This may show you have osteopenia, which is where you have lower bone density than average for your age.

If you have low bone density, you should have blood tests to check your levels of vitamin D and calcium and may be prescribed medicines called bisphosphonates. As well as vitamin supplements, there may be some lifestyle changes you can make too, to help keep your bones strong.

You can find out more about osteoporosis on the NHS website.

‘Moon’ face

Some people notice changes to their face, which can look red or puffy, or rounder. Sometimes this is referred to as ‘moon face’.

A red, round face is a symptom of a rare condition called Cushing’s syndrome, which is linked to taking high doses of steroids. You might also notice more body fat on the back of your neck, or round your shoulders. This is sometimes referred to as ‘buffalo hump .’

See your doctor or asthma nurse as soon as possible. Cushing’s syndrome can be treated. Your doctor can do tests to check levels of cortisol. You may be referred to a hormone specialist (endocrine specialist). Never stop taking your steroid medicine without advice from your doctor first.

Raised sugar levels and diabetes

Long term or continuous courses of steroid tablets can affect the way the body controls blood sugar levels. If your blood sugars stay raised, this could lead to ‘steroid-induced diabetes .’ Your doctor should arrange blood tests to check your blood sugar levels. If you notice you’re thirsty, or need to urinate more than usual, tell your doctor.

Sugar levels can go up even with a short course of steroids in someone who already has diabetes. Talk to your doctor about whether you need to do manage your diabetes differently while you’re on steroids.

The NHS has more information about diabetes, and how you can lower your risk of developing it.


Some people taking steroid tablets develop glaucoma. This is when your optic nerve in your eye becomes damaged due to a build-up of fluid.

Make sure you have regular eye tests. It’s worth catching glaucoma early, so it can be treated quickly.

Treatment will depend on the type of glaucoma you have, but you may be prescribed eye drops to reduce the pressure in your eyes, or sometimes be offered laser treatment or surgery.


Long term steroids can increase the risk of cataracts. This is when the lens in your eye develops cloudy patches.

See an optician or your GP immediately if you have any blurred vision.

If your cataracts are not too bad, stronger glasses and brighter reading lights may help for a while. However, because cataracts get worse over time, you’ll eventually need surgery to remove and replace the affected lens.

Lower immunity and resistance to infection

Taking high doses of steroid tablets can lower the body’s resistance to viruses, such as colds and flu. It can also take longer for cuts and wounds to heal.

Contact your GP or asthma nurse as soon as possible if you know you’ve come into contact with someone who has chickenpox, or shingles because the chickenpox virus can make you really unwell if you’re on steroids.

If you’re due any vaccinations, including any vaccines or boosters for COVID-19, make sure you mention the fact that you’re taking steroids, or have taken steroids recently.

This is because there’s a risk that the vaccines can be less effective while you’re taking steroids. You may need further vaccines or booster jabs to make sure you have enough protection. And live vaccines are considered unsafe in people with low immunity so check with the person giving any vaccine whether it is life or not, and make sure they are aware that you are taking oral steroids.

Find out more about COVID-19 vaccines.

Stopping steroid tablets safely

Most people on a short course of steroids can safely stop at the end of their course.
However, anyone taking long term steroids will be told to reduce the dose gradually. This is because after taking steroids for a long time, your body may not produce enough natural corticosteroids, which can lead to a condition known as adrenal suppression, also known as adrenal insufficiency.

Adrenal suppression can cause symptoms like weight loss and fatigue. It is a rare, but serious complication of being on long term steroids.

If you’ve been on steroid medicine for a long time, and you’re stopping steroid treatment, your doctor may monitor you and will consider blood tests to check your cortisol levels.
Sometimes your doctor may prescribe hydrocortisone tablets to support your body as you stop taking steroids and your corticosteroid levels drop. Hydrocortisone tablets contain a different type of steroid to the glucocorticoid steroids in prednisolone. They are sometimes used to replace a specific type of steroid produced naturally in the body. The body can stop producing this when someone is on corticosteroids for a long time. In many cases, adrenal suppression corrects itself in time.

In some cases stopping steroid medicines suddenly causes ‘adrenal crisis’. This is where levels of cortisol in your body drop dramatically. It’s a life-threatening emergency.

Always carry a steroid card

A steroid care card lets healthcare professionals know you take steroid medicines. This information is vital in emergency situations so that they know that you can’t miss doses of your steroid medication. Adrenal crisis can happen if they do not know to keep giving you steroids. The card also alerts them that your body might need extra help to deal with the injury, operation or illness.

Asking for a referral

If you need more than two courses of steroid tablets in a year, or you’re taking them all the time, you should be under the care of a specialist and be assessed for other treatments such as biologics.

Biologics (monoclonal antibodies) can reduce the need for high doses of steroids, and in some cases people with severe asthma have been able to stop taking steroid tablets all together.

“If you need to take repeated courses of oral steroids to keep symptoms under control, it’s important to keep taking them as prescribed” says Dr Andy Whittamore, our in-house GP. “But do ask your doctor or specialist for a referral so that you can be considered for alternative treatments.”

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