What is severe asthma?

Severe asthma is less common than other types of asthma, affecting around 4% of people with asthma

“We don’t understand yet why some people get asthma and some people get severe asthma,” says Dr Andy Whittamore, Asthma UK's in-house GP.

“We know that each individual with asthma can have different triggers and a different chemical reaction in their airways. That’s why Asthma UK is supporting research looking into what goes on in the body to cause severe asthma, and what makes it so much harder to control with the usual asthma medicines.”


What’s different about severe asthma?

Who gets severe asthma?

What’s it like living with severe asthma?

What’s the outlook for severe asthma?

Finding a cure for severe asthma


What’s different about severe asthma?

Severe asthma is the most serious and life-threatening form of asthma. Most people with asthma can manage their symptoms well with the usual medicines like a preventer inhaler and a reliever inhaler.

But someone with severe asthma struggles to manage their symptoms even with high doses of medicines. And sometimes it can take a while to find a combination of medicines and doses that works best for you.

Even if your asthma is difficult to control, it’s not the same as severe asthma. If you have difficult to control asthma you should be able to get on top of your symptoms with support from your GP or asthma nurse, with an action plan, regular reviews and a good routine of taking your asthma medicines.

“It took about 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, 28 

Who gets severe asthma?

Around 200,000 people in the UK have severe asthma. This is only 4% of all the people in the UK with asthma.  

Severe asthma affects both adults and children. It can develop at any age. Most people who are diagnosed with severe asthma already have an asthma diagnosis: perhaps their asthma changed over time, or developed into severe asthma because of hormonal changes, or pneumonia for example.

Some people are diagnosed right away with severe asthma, but it’s likely that they had asthma for some time before without it being diagnosed as severe. And it can take time to get a diagnosis of severe asthma.

“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, 47

What is it like to have severe asthma?

Severe asthma is an unpredictable condition and it’s different for everyone. So it’s hard to describe exactly what it’s like to have severe asthma.

The symptoms, triggers, responses to medicines, energy levels and impact on daily life are unique to each individual, plus they can change over time.

Having severe asthma can be tough. But with the right support and treatment you can hopefully feel more confident about managing your symptoms and getting on with your life.

Here are some examples of people’s experiences of severe asthma: 

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

“It took a while to find the medicines that worked with the minimum of side effects, but my current combination seems to be working – I have to use my reliever inhaler pretty regularly, but I can still get to the gym about three times a week.” – Peter, 52

“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, 44

“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, 28

Read more stories of living with severe asthma. 

What’s the outlook for people with severe asthma?

 “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 Andy.

“Some people find their symptoms improve, some go through good and bad patches and some find their asthma symptoms get worse over time. There lots of treatments around for people with severe asthma and 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.”

Airway remodelling

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.

Airway remodelling can happen as a result of poor asthma control and frequent asthma attacks. If you have severe asthma, your risk increases because you’ll probably have asthma attacks more often. Long-term exposure to pollutants including tobacco smoke can play a part too.

Whatever the reason, if you’re continually having lots of symptoms 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.

For most people, changes to the structure of your airways can be avoided with good asthma management.

COPD and Asthma-COPD overlap syndrome

Long term severe asthma can sometimes lead to a chronic lung condition called COPD (chronic obstructive pulmonary disease) or ACO (asthma-COPD overlap). 

“I wish I’d known earlier that frequent asthma attacks result in permanent damage to your lungs and cause your condition to deteriorate. I didn’t know about airway remodelling until it had already happened. 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, 44


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. 

Further support

If you’d like to talk through your concerns about severe asthma with one of our friendly asthma nurse specialists, call the Asthma UK Helpline on 0300 222 5800 or message them via WhatsApp on 07378 606728 (Monday to Friday, 9am to 5pm).


Last updated October 2019

Next review due October 2022