Diagnosing asthma in adults

Around 1 in 12 adults in the UK is being treated for asthma.

Often thought of as a condition you get when you're a child, asthma can develop at any age.

People are often surprised to find out they've developed asthma later in life, but it’s not unusual. It's known as 'late onset asthma' or 'adult onset asthma'. This type of asthma is more common in women than in men.

If you think you have asthma it's very important to make an appointment with your GP or an asthma nurse as soon as possible. Untreated asthma may be life threatening.

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What symptoms should I look for?

Common signs and symptoms of asthma include coughing, wheezing, tightness in the chest and shortness of breath.

What's triggering my asthma?

A trigger is anything that starts your asthma symptoms or makes your asthma symptoms worse. It’s possible to have several triggers and sometimes it’s difficult to work out what your triggers are.

In adults, the symptoms of asthma are less likely to be triggered by allergies, such as house dust mites, animals and pollen.

Symptoms may be triggered by:

  • flu, colds or other viral infections
  • exercise
  • heightened emotions, from laughing to getting stressed
  • hormonal changes
  • some medicines
  • certain foods
  • cold air and temperature changes 
  • cigarette smoke, chemical fumes or air pollution.

Avoiding your individual triggers, when it’s possible, can help reduce the risk of an asthma attack.

If you’ve developed asthma as an adult, it may have been caused by something at work. Occupational asthma or work-related asthma can develop very quickly or take weeks, months or years to develop.

How is asthma diagnosed?

Asthma can be complex and take time to diagnose. This is because everyone’s asthma is different. Getting a diagnosis for a child, for instance, is different from getting a diagnosis for an adult. And asthma symptoms can ‘come and go’ so it can be tricky for a GP to see the full picture.

Also, the reasons for breathlessness can vary and in adults, especially older adults, it can be more difficult to tell the difference between asthma and other conditions that cause similar symptoms such as pneumonia, heart disease, obesity, a panic attack, and chronic obstructive pulmonary disease (COPD).

If you tell your GP you think you may have asthma, they will probably start by asking questions - about your personal and family history, symptoms, workplace environment and lifestyle, for example. You may be asked to do a breathing test (lung function test) which measures how your lungs are working, and keep peak flow recordings. A number of other tests may be recommended – your GP or asthma nurse will decide which tests are suitable for you.

If you have asthma and it’s not diagnosed or managed properly, it can make it even harder for your lungs to work and, over time, make your lung function even worse.

What's a 'trial of treatment'?

If your GP or asthma nurse thinks you may have asthma, they will probably prescribe a 'trial of treatment'.

This is when you're given one or more asthma medicines to see if they help your symptoms. A trial of treatment usually lasts six to eight weeks depending on what medicines you're given. If you’re given an inhaler to use, you should be shown how to use it correctly. Even if you don’t have asthma, the benefits of taking the medicines to see whether or not you have asthma outweigh any potential side effects.

If you haven’t been given a follow-up appointment so your GP can see how you get on with the treatment, it’s very important to make one.

If you respond well to the trial of treatment (if your symptoms start to get better), it's a very good indication you could have asthma. Your treatment may be continued and you'll be monitored to make sure you’re being prescribed the lowest dose possible to manage your symptoms effectively.

If you don't respond well to the trial of treatment (if your symptoms don’t start to get better), your GP may check your inhaler technique. If you haven’t been taking it correctly, you may be asked do another ‘trial of treatment’.

Depending on the results, your GP may need to investigate other possible causes for your symptoms. If it’s unlikely you have asthma, you may be referred to a specialist.

If at any point during the trial of treatment your symptoms get worse, contact your GP or asthma nurse immediately.

What happens after diagnosis?

If you’re diagnosed with asthma, the good news is there are lots of effective medicines available to help manage your symptoms.

When you’re first diagnosed, you may need to see your GP or asthma nurse a few times to check how you’re feeling and monitor your treatment. One of the most important things you can do during this time is to download a written asthma action plan and fill it in with your GP or asthma nurse. You're four times less likely to need to go to hospital with asthma if you have one. Once you’ve filled it in, you can then take it to each appointment so it’s always up-to-date.

Once you feel as though you’re on top of your symptoms and you’re in a good routine with your medicines, it’s important to book an asthma review at least once a year – even if your symptoms are well managed and you’re feeling well. This is so your GP or asthma nurse can check your medicines in case the doses need to be changed. It’s also a chance to talk about your triggers, lifestyle and any other factors that may affect your asthma, such as hay fever.

If your GP or asthma nurse thinks you may have severe asthma (which affects around five per cent of people with asthma), the usual asthma medicines may not work well for you and you will be referred to a specialist for more tests to find out if you have the type of asthma that can be classed as ‘severe’. If you do, you will work closely with your team of health professionals to find the best combination of treatments for you.

Don't hesitate to ask for help

If you’re worried about anything to do with your diagnosis, speak to your GP, asthma nurse or pharmacist. You can also call our Helpline on 0300 222 5800 (9am – 5pm; Monday - Friday) and ask our asthma nurse specialists anything about your symptoms or treatment, your lifestyle or the way you’re managing your asthma. The better understanding you have of the condition, the better position you’ll be in to work with your GP or asthma nurse to manage your asthma well.

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We produce award-winning materials to help people with asthma understand and manage their condition more effectively. Our resources have been co-created with people with asthma, developed using the most trusted evidence, and evaluated by healthcare professionals.

Last updated November 2016

Next review due November 2019