What Does the Research Show so Far?
Asthma is a chronic inflammatory condition which involves a variety of mucosal pulmonary immune cells and whose etiology is not yet fully understood.  The current scientific literature concerning the interaction between cannabis and asthma, or more generally, allergic reactions, can be broadly divided into three categories:
- A) The effects of smoked cannabis on lung function [2-3]
- B) The difference in effects between smoked cannabis products with or without the independent behavior of smoked tobacco products [4-5]
- C) The emergent understanding of the effects of cannabis on the pulmonary system, non-specific to asthma [6-7]
The overall number of these studies is scant but growing, and the results from each one remains divided in their conclusions. [2-7]
A recent news piece published in Allure made some cogent points concerning the root inflammatory causes of asthma and how agonists of the endocannabinoid CB1 and CB2 receptors could theoretically modulate and suppress this underlying imbalance.
The article also raises the important point that receiving the unique benefits of cannabinoid consumption does not necessitate smoking cannabis products. And although this point seems simple, no study in the literature has yet made an attempt to determine what the effects of cannabis consumption via methods besides inhalation (“smoking”) might have in patients with asthma.
This represents an important avenue for future scientific approach. With the advent of pharmaceutical-grade cannabinoid preparations, such as the oromucosal spray Sativex® (1:1 THC:CBD ratio) or the FDA-approved oral solution Epidiolex® (pure cannabidiol extract), experiments can be drawn to test the potential therapeutic effects of cannabinoids while removing the main objection of the American Thoracic Society: “if you have asthma, [cannabis] smoke can cause an asthma attack leading to hospitalization and even death.” 
Patients suffering from asthma or other pulmonary conditions may get access to these potentially healing properties without the unnecessary risk of worsening their pulmonary symptoms
- Mims, J.W. “Asthma: Definitions and Pathophysiology.” Int Forum Allergy Rhinol, vol. 5 Suppl 1, 2015, pp. S2-6. [Times cited = 35, Journal impact factor 2.521].
- Chatkin, J.M. et al. “Cannabis-Associated Asthma and Allergies.” Clin Rev Allergy Immunol, vol. 56, no. 2, 2019, pp.196-206. [Times cited = 7, Journal impact factor 7.328].
- Pletcher, M.J. et al. “Association Between Marijuana Exposure and Pulmonary Function Over 20 Years.” JAMA, vol. 307, no. 2, 2012, pp.173-181. [Times cited = 198, Journal impact factor 51.273].
- Hancox, R.J. et al. “Effects of Cannabis on Lung Function: A Population-based Cohort Study.” Eur Respir J, vol. 35, no. 1, 2010, pp. 42–47. [Times cited = 114, Journal impact factor 12.242].
- Ribeiro and Ind. “Marijuana and the Lung: Hysteria or Cause for Concern?” Breathe, vol. 14, no. 3, 2018, pp. 196–205. [Times cited = N/A, Journal rank 0.868].
- Calignano, A. et al. “Bidirectional Control of Airway Responsiveness by Endogenous Cannabinoids.” Nature, vol. 408, no. 6808, 2000, pp. 96-101. [Times cited = 193, Journal impact factor 41.577].
- Ribeiro and Ind. “Effect of Cannabis Smoking on Lung Function and Respiratory Symptoms: A Structured Literature Review.” NPJ Prim Care Respir Med, vol. 26, 2016, pp.16071. [Times cited = 23, Journal impact factor 2.820].
- Drake M., and Christopher Slatore. “Smoking Marijuana and the Lungs.” Am J Respir Crit Care Med, vol. 195, no. 3, 2017, pp. 5-6. [Times cited = N/A, Journal impact factor 16.490].
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