Health advice
Smoking and asthma
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Asthma is a condition that causes breathing problems. Read more to learn about how smoking can affect asthma.
How does smoking affect asthma?

Asthma is a common condition that affects your breathing. It causes a variety of symptoms like wheezing and shortness of breath that can range from mild to severe. At its most severe, asthma can be life threatening.1

If you have severe asthma, your symptoms will be harder to control with medicines and you may have more frequent or serious asthma attacks.2

Smoking can make your symptoms worse. When you smoke, you inhale thousands of toxic chemicals through your airways and into your lungs. Smoking while living with asthma can affect your lung function and make you more likely to be hospitalised with asthma complications.3

Does second-hand smoke affect asthma symptoms?

Second-hand smoke is dangerous, causing 12,000 deaths a year in the UK.4 Even if you don’t smoke, it’s good to avoid second-hand smoke if you have asthma. The smoke from cigarettes can trigger an asthma attack.5

This is particularly important if you have or live with children. Children who grow up with parents who smoke are more likely to develop asthma have more severe symptoms.4,6

More reasons to quit

Learn more about why you should stop smoking, including the health, financial, psychological and social benefits of quitting.

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Can smoking cause asthma?

Exposure to cigarette smoke as a child makes you more likely to have asthma.5

Adults who smoke are also more likely to develop asthma. The more you smoke, the higher the risk of developing asthma as an adult is.7 However, there is no safe amount of smoking.

Can smoking cause other lung conditions in people with asthma?

People with asthma are more likely to get chronic obstructive pulmonary disease (COPD). COPD is a condition causing breathing difficulties that get worse over time.8 As symptoms worsen, it can make daily life hard to manage.9

You are especially likely to develop COPD if your asthma is poorly controlled.10

Smoking is the biggest risk factor for COPD.11 This means you’re at a higher risk of COPD if you have asthma and smoke. People with both asthma and COPD are also more likely to be hospitalised than those with either of these conditions alone.11

The best way to prevent COPD is to quit smoking.8

Can quitting smoking improve asthma symptoms?

Everyone who smokes should try to quit. Quitting smoking reduces your risk of developing a serious illness and dying prematurely. But if you have asthma, it’s even more important.

A global study found that 24% of people with asthma were current smokers.13 By quitting smoking, you can improve your overall health, but also your asthma.7

Quitting smoking improves your lung function and asthma symptoms. It reduces your chance of developing conditions like COPD and means you’re less likely to need to use as many asthma medicines.14,15

Visit your nearest pharmacy

Get support and advice from your local Well pharmacist

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Where can I go for further support and information?

Asthma and Lung UK

Information, support and resources for people with lung conditions, including asthma.

NHS Inform

Information about asthma if you live in Scotland.

NHS Website

Information about asthma, including symptoms, living with asthma and treatments to manage asthma.


1. Asthma. Published October 20, 2017. Accessed July 28, 2023.

2. What is severe asthma? | Asthma + Lung UK. Published November 30, 2022. Accessed September 4, 2023.

3. Tiotiu A, Ioan I, Wirth N, Romero-Fernandez R, González-Barcala FJ. The Impact of Tobacco Smoking on Adult Asthma Outcomes. Int J Environ Res Public Health. 2021;18(3):992. doi:10.3390/ijerph18030992

4. Britton J. Passive smoking and asthma exacerbation. Thorax. 2005;60(10):794-795. doi:10.1136/thx.2005.045336

5. Cigarettes and asthma | Asthma + Lung UK. Published May 31, 2023. Accessed September 4, 2023.

6. Skorge TD, Eagan TML, Eide GE, Gulsvik A, Bakke PS. The adult incidence of asthma and respiratory symptoms by passive smoking in uterus or in childhood. Am J Respir Crit Care Med. 2005;172(1):61-66. doi:10.1164/rccm.200409-1158OC

7. Polosa R, Thomson NC. Smoking and asthma: dangerous liaisons. European Respiratory Journal. 2013;41(3):716-726. doi:10.1183/09031936.00073312

8. Chronic obstructive pulmonary disease (COPD). Published October 20, 2017. Accessed September 4, 2023.

9. Living with. Published October 3, 2018. Accessed September 4, 2023.

10. de Marco R, Pesce G, Marcon A, et al. The Coexistence of Asthma and Chronic Obstructive Pulmonary Disease (COPD): Prevalence and Risk Factors in Young, Middle-aged and Elderly People from the General Population. PLoS One. 2013;8(5):e62985. doi:10.1371/journal.pone.0062985

11. Chronic obstructive pulmonary disease (COPD) - Causes. Published October 3, 2018. Accessed September 4, 2023.

12. Awad MT, Sankari A. Asthma and COPD Overlap. In: StatPearls. StatPearls Publishing; 2023. Accessed September 4, 2023.

13. To T, Stanojevic S, Moores G, et al. Global asthma prevalence in adults: findings from the cross-sectional world health survey. BMC Public Health. 2012;12:204. doi:10.1186/1471-2458-12-204

14. Thomson NC, Chaudhuri R, Heaney LG, et al. Clinical outcomes and inflammatory biomarkers in current smokers and exsmokers with severe asthma. Journal of Allergy and Clinical Immunology. 2013;131(4):1008-1016. doi:10.1016/j.jaci.2012.12.1574

15. Chaudhuri R, Livingston E, McMahon AD, et al. Effects of smoking cessation on lung function and airway inflammation in smokers with asthma. Am J Respir Crit Care Med. 2006;174(2):127-133. doi:10.1164/rccm.200510-1589OC

Published: October 2023

Next review: October 2026

Reviewed by: Connie Whewall

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