Abstract
INTRODUCTION: The use of cannabis, cocaine or heroin can be responsible for many respiratory complications including asthma. OBJECTIVES: The aim of this systematic literature review of data was to expose the relations between cannabis, cocaine or heroin use and asthma. RESULTS: Cannabis, cocaine or heroin use by inhalation may be responsible for respiratory symptoms (cough, wheezing), asthma onset, acute asthma exacerbations (which may require intubation and invasive ventilation) or deaths related to asthma. Lower adherence to asthma treatment is also observed. Cannabis induces a rapid bronchodilator effect. In contrast, its chronic use may induce a decrease in specific airway conductance. Studies on forced expiratory volume in one second (FEV1) reduction or decline are discordant. CONCLUSION: Cannabis, cocaine or heroin use must be considered in cases of acute respiratory symptoms or asthma exacerbation in young persons and practitioners must help illicit substance users to stop their consumption.