Non-allergic asthma

Non-allergic asthma

There are two main types of asthma: allergic asthma and non-allergic asthma. Non-allergic asthma is more common among adults than among children and the symptoms appear later in life. Women are more often affected than men and many cases of non-allergic asthma are triggered by an infection of the airways.

It is likely that both heredity and environment determine who is affected by non-allergic asthma. Scientists do not know all of the risk factors that lead to asthma, but it is well known that smoking may cause non-allergic asthma in both children and adults. Children of women who have been smoking during pregnancy are, to a larger extent, born with more narrow airways than other children. Being overweight is another risk factor associated with both allergic and non-allergic asthma and if you are both overweight and a smoker the risk of asthma is even larger. Poor ventilation, increased hygiene, air pollution and widespread use of antibiotics are also suspected to contribute to the increase of asthma over the last 25 years.

What triggers non-allergic asthma?

While allergic asthma is triggered by allergies which in most cases are hereditary, it is irritating substances called trigger factors of the environment that provoke non-allergic asthma. Even allergic people with asthma may have asthma attacks triggered by smoking or strong smells for example. 

The most common triggering factors for non-allergic asthma are:

  • Smoking
  • Infections of the respiratory tract
  • Cold air
  • Weather changes
  • Irritating substances like perfumes and exhaust fumes 
  • Physical exertion (exercise-induced asthma)
  • Certain medicines (painkillers containing acetylsalicylic acid, inflammation inhibiting painkillers within the NSAID-group, and beta blockers used for high blood pressure and heart disease)

How can I avoid triggering non-allergic asthma?

If you have asthma you should not be smoking and preferably neither should anyone else around you, at least not indoors. Tobacco smoke is the most common cause of a polluted indoor environment, and passive smoking is almost as dangerous as active smoking. The optimal solution is to avoid smoky environments completely if you can. And do not let anyone smoke around your children. 

Cold weather and dry air put a strain on the mucous membranes and are problematic for many asthmatic people. In addition, cold air circulates less, which means that there are more exhaust fumes and other pollutions in the air during wintertime. The great temperature difference between indoor and outdoor environments can also give rise to problems. This does not mean that you have to stay indoors and wait for spring if you have asthma. As long as you make sure that your asthma is well controlled by medication and you avoid cold shocks. 

Tips for cold days:

  • Do not rush out into the cold weather, but stop for a minute and breathe calmly through your nose until your airways have had a chance to get used to the temperature
  • If you suffer from nasal congestion it is good to treat it before going outside, in this way you will be able to breathe through both your nose and mouth
  • Cover your mouth and face with a scarf to protect you from the cold
  • Adjust your work out according to temperature. Remember that the stress of the mucous membranes increase during prolonged exposure to cold weather
  • Avoid exercising in cold air if you suffer from exercise-induced asthma since the asthma is worsened by the cold
  • Use a heat exchanger during longer outdoors stays, it helps in heating the air you breathe in. It comes either in shape of a hood that is pulled down covering your mouth and nose, or as a breathing mask

Other substances triggering asthma

As an asthmatic you should avoid using spray paints, paints and cleaning products with a strong odour when you are indoors and make sure that your home is well ventilated. You should also not use perfumes, perfumed lotions or other products with strong odours that may irritate your respiratory tract. 



UK/GEN/15/0055a         Date of preparation: December 2015


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