The beneficial effects of cannabinoids in the treatment of respiratory diseases have been drawing researchers’ attention for several decades. Asthma is a complex disease entity characterized by a variable course, the treatment of which requires the continuous search for alternative, adjuvant treatment strategies designed for patients refractory to available pharmacotherapies. Cannabinoids exert certain physiological responses in the respiratory system due to their immunomodulatory properties and the strong presence of the endocannabinoid system in the lungs. In animal model studies, THC and CBD seem to counteract bronchoconstriction and inhibit pro-inflammatory mediation, respectively, which highlights their possible future contribution to the treatment of respiratory and allergic diseases, such as asthma.

However, there are controversies regarding the health consequences of cannabis usage, the extracts’ proportions, or equally safe and effective routes of administration, especially considering the alarming reports indicating an increased risk of asthma development among recreational cannabis smokers. The purpose of this review is to analyze the available literature on the influence of the endocannabinoid system, phytocannabinoids, and their modes of action on asthma pathogenesis in an attempt to assess their potential clinical relevance and determine future research directions.