Cannabis smoke can trigger asthma attacks and allergic reactions, and these risks are often overlooked | Research

The takeaway

A review found marijuana use is associated with increased asthma symptoms, allergic reactions, and more frequent medical visits, making cannabis an underrecognized precipitant of respiratory and allergic disease.

Allergists, pulmonologists, asthma patients who use cannabis, and primary care providers.

Underrecognized asthma trigger

What the researchers found

Multiple studies associate marijuana use with increased asthma symptoms and other allergic disease manifestations, as well as increased frequency of medical visits. Cannabis can cause allergic reactions through direct sensitization. The review emphasizes that cannabis is an underrecognized precipitating factor for acute asthma and allergic attacks.

Why it matters

As cannabis use normalizes, clinicians may not think to ask about it when evaluating asthma exacerbations or allergic reactions. Cannabis may be an unrecognized trigger in patients with poorly controlled asthma or unexplained allergic symptoms.

The numbers in context

Cannabis inhalation is the most common form of use. Pulmonary complications may be the most common form of drug-induced pulmonary disease worldwide. Multiple studies documented increased asthma symptoms and medical visits.

How the study worked

Narrative review of English, Spanish, and Portuguese literature from 1970-2017 on the relationship between cannabis use and asthma/allergic diseases.

What this study cannot tell us

Narrative review without systematic methodology or meta-analysis. Much of the evidence is observational. Long-term effects in allergic asthma patients are not well studied. The review cannot distinguish between smoked cannabis effects and inherent allergenicity.

How to read the evidence

Rated moderate because the review covers multiple decades of literature, though systematic methodology was not used.

When this study was published

Published in 2019 reviewing literature through 2017.

The bigger picture

Cannabis allergy is a real and growing phenomenon. As more people are exposed through legalization, both direct sensitization (from the plant) and inhalation-triggered asthma may become increasingly common clinical presentations.

Questions still open

Would non-smoked cannabis (edibles, tinctures) avoid the respiratory triggers? How common is true cannabis allergy versus smoke-irritant effects? Should allergists routinely screen for cannabis use?

Common questions

Can cannabis trigger asthma attacks?

Yes. Multiple studies document increased asthma symptoms and medical visits in cannabis users. Both the smoke itself and allergic sensitization to the plant can trigger respiratory problems.

Is cannabis allergy real?

Yes. Cannabis can cause genuine allergic reactions through direct sensitization to the plant. As use becomes more widespread, cannabis allergy diagnoses are expected to increase.

Read the original research

Cannabis-Associated Asthma and Allergies.

Clinical reviews in allergy & immunology, 56(2), 196-206

View on PubMed ↗Publisher’s paper ↗

Citation

Chatkin, J M; Zani-Silva, L; Ferreira, I; Zamel, N. (2019). Cannabis-Associated Asthma and Allergies.. Clinical reviews in allergy & immunology, 56(2), 196-206. https://doi.org/10.1007/s12016-017-8644-1