1 in 20 people with asthma have severe asthma

What is severe asthma?

Severe asthma is much less common than other types of asthma, affecting around 5% of people with asthma

What is severe asthma?

Asthma UK's in-house GP, Dr Andy, explains what severe asthma is, and how it's different to mild or moderate asthma.

Video: What is severe asthma?

Asthma UK's in-house GP, Dr Andy, explains what severe asthma is, and how it's different to mild or moderate asthma.
Transcript for 'What is severe asthma?'

0:00 Hi. My name is Dr Andy Whitmore. I'm Asthma UK's in-house GP. I'm here to talk to you about severe asthma. Here are some key points for you to take away. There

0:10 are 250 thousand people in the UK with what we call severe asthma. Severe asthma is a type of asthma where, despite people taking their regular preventer medication on a regular basis

0:20 understanding their triggers, and looking after their asthma as best as they can, they're still getting asthma symptoms. This is what we call severe asthma.

0:27 Severe asthma affects 1 in 20 people in the UK with asthma. That's about quarter of a million people. We still don't know enough about severe asthma; we don't quite understand why it affects some people and not others, and why some

0:39 people develop it later in life or at different times in their life. There is some good news about severe asthma, your specialist can now prescribe medications which really revolutionise some people's lifestyles. Asthma UK are really

0:53 pushing hard to try and get more medication that can help even more people with severe asthma.

Someone who is diagnosed with ‘severe asthma’ has a specific type of asthma where symptoms do not get better even when they take the usual medicines regularly and correctly, and where other causes and triggers for the symptoms have been ruled out as much as possible. Severe asthma needs specialist assessment and very different support and treatments – about 250,000 adults and children in the UK are diagnosed with it.

How is severe asthma different from other types of asthma?

“We know that each individual with asthma can have different triggers and a different combination of chemicals in the blood and airways involved, but we don't understand yet why some people get asthma and some people get severe asthma," says Dr Andrew Whittamore, Asthma UK’s in-house GP. "People with severe asthma have symptoms that are much harder to control because they don't improve with the usual asthma medicines even when they're taken as prescribed. That’s why Asthma UK is supporting lots of research looking into the reasons.”

A few of the current theories about why severe asthma occurs are:

  • Some people’s airways may be too inflamed for the usual medicines to work well enough.
  • Some people’s inflammation could be caused by chemicals that aren’t blocked or controlled by current medicines and we don’t have the right medicines to control all of the chemicals that cause the inflammation.
  • In some people, asthma symptoms are not caused by high levels of allergy-related cells and chemicals, so the usual medicines to tackle these allergic causes don’t work. These people might have 'eosinophilic asthma' where inflammation is triggered by high levels of a particular white blood cell called an eosinophil.

How is ‘severe’ asthma different from ‘difficult to control’ asthma?

Around 17% of people with asthma have frequent and sometimes potentially life-threatening asthma attacks but this includes two very different groups:

  1. people with a medical diagnosis of severe asthma (this group makes up approximately five per cent of the total number of people with asthma)
  2. people with difficult to control asthma (this group is much bigger, making up approximately 12% of the total number of people with asthma)

If you have difficult to control asthma, current asthma medicines will work to bring your asthma symptoms back under control once you find ways with your GP and asthma nurse to get your routine working for you.

If you have severe asthma, there are still lots of things you can do, but you’ll need extra specialist care and support as well. The combination of looking after yourself, and getting the right support, and the right treatments, is key.

Who gets severe asthma?

You can develop severe asthma at any age. Your asthma can change to become severe over time, or it can be triggered more suddenly by certain factors such as pneumonia or hormonal changes. Most people who are diagnosed with severe asthma already have an asthma diagnosis. Some people are diagnosed right away with severe asthma, but it’s likely that they had asthma for some time before without it being officially diagnosed as severe.

“I was diagnosed with asthma at 35, but my GP said I’ve probably always had it. I spent a lot of time in hospital with chest infections and croup as a child. In the lead up to my severe asthma diagnosis, aged 40, I had pneumonia and started getting a lot of infections. My asthma changed and I could barely walk or move.” - Kate Harris, 47

What is it like to have severe asthma?

It’s impossible to pinpoint exactly what it’s like to have severe asthma because the condition is different for everyone and unpredictable. The symptoms, triggers, responses to medicines, energy levels and impact on daily life are unique to each individual, plus they can change over time…

Here are a few experiences people with severe asthma have shared with us:

“I have symptoms all the time, and it stops me doing a lot of things. I can’t go out for a walk during pollen season, and often I can’t do even gentle exercise. I don’t do much socialising.” - Sean Michael, 44

“I have withdrawn from lots of things as keeping as healthy as possible takes time, energy and all of my strength. I'm usually asleep by 9.30 to cope. My meds help to some degree but exercise has definitely improved my health.” - Kate Harris, 47

“Over the course of a few years I went from rock climbing, mountain biking, marathon running and teaching kids dance to being unable to walk upstairs. On bad days I couldn’t walk the 18 steps from my bed to my bathroom. I also found talking difficult. I would be breathless and try to disguise it around people and have to visit toilets to use my inhaler." - Vickie Taylor, 27

“I’m on a good combination of medicines now – I have to use my reliever inhaler pretty regularly but I can still get to the gym around three times a week. It took a while to find the right combination of medicines to find out what worked with the minimum of side effects, but my current combination seems to be working.” - Peter Naylor, 52

“Having severe asthma doesn’t stop me being active. I do a lot of aerial gymnastics so sometimes I’ll be hanging upside down in mid-air from a silk and realise I need my inhaler. I make sure it’s always on the side of the crash mat, and we have a buddy system (two people to each silk) so there’s always someone who can help me out.” - Abi Bettle, 28

You can find more stories from people with severe asthma here.

Are there special medicines for severe asthma?

Yes, there are some special medicines and treatments available. There’s also a great deal of scientific research going on into the different types of asthma with a view to finding effective treatments for everyone with severe asthma. The good news is that new treatments which target specific subtypes of severe asthma are now available, for example Xolair which targets severe allergic asthma, and Mepolizumab and Reslizumab which both target eosinophilic asthma. 

You will need to work with your healthcare professional to find a combination of medicines and doses that helps you manage your symptoms to the best level.

As well as taking the asthma medicines that people with asthma commonly take, probably at higher doses, your healthcare professional may also prescribe extra treatments that other people with asthma don’t need.

Because there is no set treatment combination that works for everyone, it can take time to find the right treatment plan for you. For this reason, you will probably be referred to a specialist alongside your GP or asthma nurse.

One medicine commonly used to reduce inflammation in the airways is steroids. For most people with asthma, steroid tablets are only usually prescribed for a short time when the inflammation in their airways is high, and their symptoms are considerably worse than normal. But if you have a severe asthma diagnosis, the inflammation and sensitivity of your airways is likely to be worse a lot of the time, so you may need steroid tablets along with inhalers, in the long term, to help keep this under control. If you’re prescribed steroids in the long term, you’ll need specialist advice and support.

Some people with severe asthma don’t respond to steroids. This is called ‘steroid-resistant asthma’. In this case, your doctor will prescribe other types of medicine. You can find more information about the different medicines for severe asthma here.

“It took around five years to find the best combination of medicines for me – I spent six or seven months on each one, so I felt I’d given it a fair go. My asthma nurse is always working to help me find a balance of medicines. I see her every eight to 12 weeks, whether or not there’s a problem.” - Abi Bettle, 28

What’s the outlook for people with severe asthma?

If you’ve been diagnosed with severe asthma, or think you have it, you may be concerned about what it means for you in the longer term.

"Because severe asthma is so unpredictable in the treatments it responds to and the course it takes, the long term outlook is different for everyone," says Dr Andrew Whittamore, Asthma UK's in-house GP. "Some people find their symptoms improve, some go through good and bad patches and some find their asthma symptoms get worse over time. The good news is that there are lots of treatments around for people with severe asthma and that your team of healthcare professionals will work with you to find the right ones for you so you can have the best quality of life possible in the long term."

The risk of long term damage to your lungs

One of the possible long term effects of severe asthma is something called ‘airway remodelling’. This is where your airways become thicker over time, so the airway itself is narrower, making it harder to breathe. This can happen as a result of frequent asthma attacks. If you have severe asthma, your risk increases because you’ll probably have asthma attacks more often.

It's not clear what causes airway remodelling but lots of studies suggest inflammation, long term exposure to pollutants including tobacco smoke and/or poor asthma control can play an important part.

You might have poor asthma control because it's taking time to find the right medicines that work for you, or perhaps you're not taking your medicines exactly as prescribed.

Whatever the reason, if you're having lots of symptoms all of the time over a long period of time then there’s a risk your airways will become permanently narrowed, scarred and inflamed, which can mean your symptoms get worse.

How you can help reduce your risk of long term lung damage

Changes to the structure of your airways can be avoided with good asthma management. While this is often easier said than done if you have severe asthma, because it can be a challenge to find the right treatment, there are still lots of things you can do to help manage your symptoms. The top three things you can do:

  1. Go for regular reviews of your medicines to check how well they’re working to reduce your symptoms.
  2. Work out which pollutants and irritants, such as dust, fumes and pollen, affect you so you can avoid them wherever possible.
  3. Quit if you smoke – you can find lots of top tips here.

"I wish I’d known earlier that frequent asthma attacks cause permanent damage to your lungs and cause your condition to deteriorate. I would never have moved to London, and avoided stress, if I’d known – but I didn’t know about airway remodelling until it had already happened. I saw hundreds of specialists during my childhood and no-one mentioned it – one suggested that I move to the beach, but didn’t say why.

"When I asked about it, I was told ‘it’s not a hard and fast rule’ and that it doesn’t happen to everyone, but it does happen, and people should be told. It’s an extremely serious condition – I want to tell people to avoid scarring to their lungs at all costs. I would have lived very differently – stayed away from stress, people who smoke, cats, and pollen, and lived a quiet life. Instead I took all those risks and just battled the symptoms with steroids." - Sean Michael, 44

In cases where airway remodelling has already happened, a treatment called bronchial thermoplasty may help.

Complications of severe asthma

Long term severe asthma can sometimes lead to a chronic lung condition called COPD (chronic obstructive pulmonary disease) or ACO (asthma-COPD overlap). You can find out more about both these conditions here.

Do you think you might have severe asthma?

If you’re getting asthma symptoms often or your symptoms are getting worse, this is a warning sign your risk of an asthma attack is higher, so make an appointment to see your GP or asthma nurse urgently to talk about your asthma.

It may be that your medicines need to be reviewed, or that you need to get into a different routine to help you remember to take them. Or your GP or asthma nurse might need to check your inhaler technique – if you’re not using it in the right way, you won’t be getting the full dose of the medicine into your lungs, where it’s needed. Use a written asthma action plan to help you manage your asthma well. Most of the time, difficult asthma symptoms can be treated, and with the right medicines and support, you can get back on track.

But if you’re getting lots of symptoms even though you…

  • Have had your medicines reviewed by your GP or asthma nurse
  • Have had your inhaler technique checked
  • Are taking your medicines every day exactly as prescribed
  • Are following your written asthma action plan

… it’s important to explain all this to your GP and ask them to refer you to a specialist clinic for tests to see if you have severe asthma.

If you’d like to talk through your concerns with one of our friendly asthma nurse specialists, call our Helpline on 0300 222 5800 (9am-5pm; Monday-Friday).

Finding a cure for severe asthma

Asthma UK is working with scientists, researchers and people with asthma to find new treatments for severe asthma, and ultimately, a cure. In our landmark Severe Asthma report, we explain how we’re working towards this goal and how it will help people to live longer and live better. Find out more about Asthma's UK research into severe asthma here.


Last updated October 2016

Next review due October 2019