Smoking and Asthma: Triggers, Risks and Quitting

Asthma affects people of every age, and the Lung Health Foundation describes it as a chronic, life-long condition that makes it harder to breathe. Smoke from tobacco reaches the airways of the person smoking and of anyone nearby. This page sets out what Canadian health organizations say about that, and where they stop saying anything.

Why smoke matters for asthma

Asthma Canada sorts triggers into two groups. Allergic triggers cause swelling in the airways. Symptom triggers, which it says “include smoke, exercise, cold air,” do not generally cause swelling but can provoke twitchy airways. A smoky room can therefore set off coughing or wheezing in someone whose asthma is otherwise quiet.

The Lung Health Foundation lists tobacco and wood smoke among indoor irritants. Health Canada separately lists lung and respiratory problems among the increased risks for people who smoke. For the wider picture of what smoking does to the lungs, see smoker’s lungs and chronic bronchitis.

Second-hand smoke

Health Canada’s risk page says children exposed to second-hand smoke face “more frequent and more severe asthma attacks” if they already have asthma. It explains that children are especially vulnerable because their breathing and immune systems are still developing. Adults are included too: the same page lists breathing problems, such as more severe asthma, among the effects on adults.

Asthma Canada’s home advice is short. It says to make your home completely smoke free. It also suggests planning ahead for visits where cigarette smoke is likely. Our page on secondhand smoke health effects covers exposure in more detail.

Smoke and asthma risk in children

The Public Health Agency of Canada lists exposure to tobacco smoke, including exposure before birth, among asthma risk factors. The Lung Health Foundation names not smoking, especially during pregnancy, and not allowing smoking in the house when children are small, as ways to lower a child’s chance of developing asthma.

Quitting and where to get help

If you have asthma and smoke, or share a home with someone who does, quitting removes one trigger from the air you both breathe. The sources we read do not measure how much quitting improves asthma control, so we do not give a figure or a timeline here.

Support is available in Canada. The Lung Health Foundation points to a quit plan and readiness assessment on its site, and it offers a patient support line at 1-888-344-LUNG (5864). Our guide to what is free for you and the list of free quit help by province show programs and products that cost nothing or are subsidized. A pharmacist can also explain quit medications.

What the home advice covers

The advice from Asthma Canada and the Lung Health Foundation points the same way. Keep smoke out of the places where a person with asthma, especially a child, spends the most time. Asthma Canada frames this both as a home measure and as a planning step before visits. If you smoke and want to stop, our page on free quit help by province is a place to start, and your pharmacist can answer questions too.

When to get medical help

The Lung Health Foundation says to see a healthcare provider for a proper diagnosis if you have asthma symptoms. In an emergency, call 911. For non-urgent questions, your doctor, pharmacist or the 811 health line can help. This page is general information and not personal medical advice.

What we could not confirm

• Whether and how quickly quitting smoking improves asthma symptoms or control. The Canadian pages we read did not say.
• How asthma and smoking combine to affect lung function over time, including any comparison with COPD. The pages we read did not cover it.
• HealthLinkBC’s asthma pages did not discuss smoking in the text we could read, so we did not use them as a source.