Other Effects of Smoking Marijuana
Dr Powell noted that there is evidence demonstrating stress and injury to the lungs after exposure to any smoked product, aside from the issue of lung cancer risk.2-4
“Lung cells have strong capabilities to respond to injury, and the outcomes include full repair, cell death, airway inflammation, lung fibrosis, permanent changes to the cell DNA, and cancer,” Dr Powell explained. “These short-term and long-term responses can occur when smoking cigarettes, E-cigarettes, marijuana, cigars, and water pipes.”
Various factors determine an individual’s response to these exposures, according to Dr Powell. Susceptibility to lung injury and lung disease is determined, in part, by genetics, but there is a lack of data to enable prediction of which smokers will develop cancer.
“My advice is not to smoke, period,” Dr Powell said. “There are alternative approaches to access marijuana other than through smoking, and there is no evidence to date—nor is there likely to be—that oral or topical use of marijuana products will injure the lungs.”
In the context of medical marijuana use for symptom relief in patients with cancer,10 however, Dr Abrams recommended that “if patients want better control over the onset, depth, and duration of the effect, inhaling is probably better than ingestion.”
“Further research is indicated to better understand the impact of different marijuana cigarette products and different approaches to smoke marijuana,” Dr Powell said. In addition to being useful for health care providers, “this information may be useful to those who cannot or will not quit,” he said.
Disclosures: Dr Abrams and Dr Powell have no relevant disclosures.
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