[Inhaled marijuana and the lung, a toxic cocktail?]

Unlike the well-documented effects of tobacco smoke on the lung, the effects of cannabis smoke remain controversial, the main bias consisting in co-consumption of tobacco. That said, the composition of joint smoke is close to that of cigarettes, containing many compounds that are carcinogenic and/or alter the respiratory epithelium. Confirmed respiratory effects in chronic cannabis smokers include aggravated chronic bronchitis symptoms, a cumulative effect with tobacco on COPD and emphysema occurrence, an increased risk of bullous emphysema, and pneumothorax with heightened risk of recurrence after pleural symphysis. Recent prospective studies have shown a negative impact on lung function, with not only damage to the airways, but also DLCO alteration and an accelerated drop in FEV1. Finally, cannabis smoking is very common among young patients with lung cancer. Its consumption could lead to a different lung cancer profile, potentially more undifferentiated and less accessible to targeted therapy. Questioning about cannabis consumption must be systematic and targeted medical care should be offered.