A current study was done to establish the collective and independent effects of tobacco and cannabis smoking on respiratory symptoms and chronic obstructive pulmonary disease (COPD) within the general population. COPD is a progressive (which means it gets worse with time) lung disease that makes it hard to breathe. COPD symptoms include chronic coughing, mucus production, wheezing, shortness of breath, and chest tightness. The leading cause of COPD is tobacco smoke. The above mentioned study evaluated 878 people aged 40 and older and assessed their respiratory history, use of tobacco and use of marijuana. They performed lung function tests before and after using medication that opens up the lungs.
The findings: “Smoking both tobacco and marijuana synergistically increased the risk of respiratory symptoms and COPD. Smoking only marijuana was not associated with an increased risk of respiratory symptoms or COPD.” (Tan, et al, Canadian Medical Association Journal, 4/14/09; 180)
Despite these findings, most physicians still recommend that medical marijuana patients do not smoke their medication and instead use vaporizers, edibles, and/or tinctures. It is clear from this study that the damage that smoking tobacco can cause is significant (which we all knew before anyway!) and it can be worsened if you also smoke marijuana.