Asthma is a common, long-term condition which effects the lungs.  People with asthma have airways (or breathing tubes) that are more sensitive and can become inflamed and narrow on exposure to certain triggers.  This can lead to difficulty in breathing.

Asthma commonly starts in childhood, but it is possible to develop asthma at any age. The causes of asthma are not fully understood.  We do know that both the environment (e.g., exposure to tobacco smoke) and genetics have a role to play in who develops asthma. Asthma cannot be cured, but it can be controlled with medication and by following an asthma management plan.

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Information on symptoms, diagnosis and treatment.

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Allergy and Asthma

There is a link between asthma and other allergic conditions including eczema, Allergic rhinitis, and food allergy. People with allergic rhinitis (which affects the nose and can be seasonal or all year round) or a family history of allergy have an increased likelihood of developing asthma (see Allergy UK’s factsheet on Allergic Rhinitis). It is important if you have both allergic rhinitis and asthma that your nasal symptoms are well controlled. Poorly controlled allergic rhinitis can lead to the development of asthma or make asthma symptoms.

Could it be asthma?

Asthma symptoms vary between people and can come and go.  To be diagnosed with asthma you need to have two or more of the following

  • Feeling short of breath / breathlessness
  • Cough (day or night)
  • Wheeze
  • Chest tightness

These symptoms can also be caused by other conditions, so if you suspect you may have asthma you should see your GP as soon as possible.

Diagnosing asthma

Diagnosing asthma is not always easy and it may take a few appointments before diagnosis. Your GP will ask questions about your symptoms, when they started, how long they last for and possible triggers. They will listen to your chest with a stethoscope. They may arrange for you to have a breathing test called spirometry (which involves blowing through a tube to see how well your lungs are working) or they may give you a peak flow meter to use at home.

What causes my asthma to get worse?

There are many triggers for asthma symptoms and attacks. It is important to work out what your triggers are – there may be more than one.  It is not always possible to avoid triggers such as a cold, flu or other viral infections, pollution, or some allergens (see table 1). Exercise can also be a trigger for some people with asthma. Sometimes people get mixed up with breathlessness they have with exercise which is normal.  Your doctor, nurse or pharmacist can give advice on how to manage triggers, how to avoid or reduce them and medication to be taken if exposed.

Between 1- 5% of people with asthma are not able to take a group of medications called non-steroidal anti-inflammatory drugs e.g., ibuprofen. If you take these medicines and think they trigger your asthma you may have an allergy to this medication. Speak to your GP, Nurse or Pharmacist as there are other medicines that you may be able to take. Always check the information provided with your medications to make sure they are suitable for people with asthma.

Key Message: Identifying your personal trigger(s) helps you to avoid or reduce exposure and improve your asthma symptoms.

Occupational asthma happens when people are exposed to substances through the environment at work. These substances act as an asthma trigger or may cause adult asthma. If an adult develops asthma, they should be asked about their work as this might be the cause. Dust and chemicals are common triggers in jobs such as hairdressing or manufacturing. Mould is another common problem, e.g., from compost and soils.

Common asthma triggers


  • Weather changes
  • Irritants, e.g., perfume
  • Indoor air quality
  • Second hand smoke / vaping


  • House dust mites
  • Animals and pets
  • Pollen
  • Mould and fungi
  • Food


  • Cold / viral infection
  • Smoking
  • Hormones
  • Sexual activity
  • Alcohol
  • Exercise
  • Medications and recreational drugs
  • Occupation 
  • Stress and anxiety
  • Emotions e.g., laughing etc.

Key Message: Having a cold, flu or other viral infection may trigger asthma symptoms. Keeping fit and healthy, avoiding contact with those who are unwell and getting regular flu/Covid vaccines is recommended.


Everyone with asthma needs to use an inhaler of which there are many types containing measured doses of different medications. The two main types of inhalers are called preventers and relievers. There are also combination inhalers which contain both a long-acting reliever and a steroid preventer. It is important you are shown how to correctly use the type of inhaler that is prescribed for you.

Reliever inhalers

Reliever inhalers are used as and when asthma symptoms are experienced. Everyone with asthma needs to have a reliever inhaler prescribed. If you are using this type of inhaler regularly, it means your asthma is not controlled and you need to seek advice from your Asthma Nurse or GP.

Preventer inhalers

Preventer inhalers contain a steroid which works by reducing swelling and inflammation in the airways. They help prevent asthma symptoms and should be taken as prescribed daily to build up a protective effect.


Using a spacer (a holding chamber that fits on the end of an inhaler) is an effective way of ensuring your asthma medication reaches the right place with the correct dose. Use of a spacer is recommended as part of your asthma management. This is because the press and breathe action is important for effective use of an inhaler.

Do I need an annual asthma review if my asthma is not bothering me?  

If you haven’t already arranged an annual asthma review with your GP or Asthma Nurse, it would be advisable to do so. This provides the ideal opportunity for asthma medication to be reviewed, inhaler technique to be observed and to ensure your personal asthma action plan is up to date. If you are having troublesome hay fever symptoms this is a good time to discuss any concerns as uncontrolled allergic rhinitis or hay fever can make our asthma symptoms worse.  In addition to inhalers, oral or nebulised medication may be required.

If you are required to take a combination of therapies an asthma management plan is a useful guide to what to take and when.

Personalised Asthma Action Plans (PAAPS)

Asthma treatment consists of 5 steps that relate to how severe your symptoms are from mild (Step 1) to severe (Step 5). Treatment is stepped up or stepped down as needed. Having a written asthma action plan helps you to recognise when symptoms become worse and what to do if you have an asthma attack. An asthma action plan can be viewed and printed from the following link.

Personalised Asthma Action Plans

Key Message: Asthma medication is only effective if taken properly. When you see your GP, Asthma Nurse or Pharmacist ask for a review of your inhaler technique (even if you have been using your inhaler for a long time it may not be effective). If you require more information on inhaler technique including videos showing correct techniques for different types of inhalers visit Asthma UK website for further information.

How can I manage my asthma effectively?

Good control starts with taking your asthma medication correctly, following your personal asthma action plan to identify when your asthma is not well managed and the avoidance of triggers. If you feel your asthma is not well managed it is important to see your GP or Asthma Nurse without delay. They may advise you on a change of medication or increased dose. It is important to be aware that, if symptoms are not well managed, they can increase quickly and result in a visit to A&E or a hospital admission.

How to recognise if your asthma is getting worse

  • Coughing or wheezing more than normal
  • Finding it difficult to breath, talk or sleep
  • Reduced peak flow measurements
  • If your reliever is not helping and/or you need to use more than normal
  • You are becoming exhausted by the effort of breathing

What happens in an asthma attack?

In an asthma attack the muscles around your airways can become swollen and inflamed with increased mucus production resulting in one or more of the following symptoms: difficulty breathing, difficulty speaking, experiencing a wheeze, blue colour to the lips and feeling distressed.

What do I do if I am having an Asthma Attack?

Immediately take 1 puff of your reliever inhaler, repeating 1 puff, if required, every 30-60 seconds, up to a maximum of 10 puffs. Try to remain calm and sit upright (this allows you to breathe easier)

If you feel worse, or do not feel any better after 10 puffs call an ambulance (this ensures medical help is on its way). If the ambulance takes longer than 15 minutes to arrive, then repeat step 1.

Key Message: If your symptoms improve after using your inhaler and you don’t need to call an ambulance, it is important to make an appointment that day with your GP or Asthma Nurse who will be able to provide advice on your asthma control.