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What is asthma?

Asthma is an inflammatory condition in which airways narrow due to hyper- responsiveness to a wide range of stimuli. This may result in coughing, wheezing, chest tightness, and shortness of breath and an increase in sticky mucus production (phlegm). Narrowing of the airways is usually reversible (either spontaneously or with medication) leading to intermittent symptoms, but in some people with chronic asthma, the inflammation may lead to irreversible airflow obstruction.  

The human body produces hormones called steroids that help to regulate inflammation. This process tends to switch off when you sleep, so asthma is often worse at night and first thing in the morning.

In early childhood, asthma is more common in boys than in girls, but by adulthood, the sex ratio is reversed. Approximately 60% of adults with asthma in the UK are women.


The probability of someone having asthma could increase with:

  • History of atopic disorder (example hayfever,eczema)
  • Family history of asthma and/or atopic disorder.

Making a diagnosis of asthma is a process which is different in adults and children. The process of assessment should result in an accurate diagnosis in order to ensure the person receives appropriate treatment.  The diagnosis of asthma is based on:

  • Signs and symptoms
  • Clinical history
  • Breathing tests such as spirometry with or without bronchodilator reversibility, pulmonary function tests, peak expiratory flow, nitric oxide exhalation test, bronchial hyper-responsiveness using methacholine, exercise or mannitol
  • Other tests, including tests for atopy (skin prick tests for allergies), chest x-ray and blood tests

Allergic Asthma
Occurs when a person is exposed to an allergen which irritates the airways, triggering asthma symptoms. Damp, house dust mite, Mould, roaches, pollens (seasonal) and pet dander are common allergens.

Non allergic Asthma
Occurs due to irritants, such as cold air, pollution, chemical fumes, Flu and other viral infections.

Occupational Asthma
Occurs particularly in work places such as bakery's, laboratory's, farming or manufacturing plants etc. Other symptoms that can be linked to occupational asthma are rhinitis (sneezing, itchy, runny nose) or conjunctivitis (itchy, red, and inflamed eyes). Occupational Asthma symptoms improve on the days when not at work and get worse after work, or sleep disturbances after work.

Exercise Induced Asthma
Occurs following physical exertion or sports leads to coughing, difficulty breathing and chest tightness that improve when exertion stops.​

Drug induced Asthma
Drugs such as Aspirin and other NSAIDs (example ibuprofen) may induce bronchospasm (tightening of the airways) and, in rare cases, this reaction can lead to aspirin-sensitive asthma.  Beta blocker medications including eye drops are contra indicated in patients with asthma.

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