“Cannabis is the most commonly abused illicit drug and the smokers are at the risk of lung infections, bullous emphysema and lung cancer. However, no evidence about the outcomes of lung transplantation (LTx) utilizing the lungs from such donors is available in the literature.

The history of donor cannabis smoking does not appear to affect early and mid-term outcomes after LTx and potentially improve the donor pool. As it does not seem to negatively affect the outcomes after LTx, it should not be per se considered a contraindication for lung donation.”

https://www.ncbi.nlm.nih.gov/pubmed/28077504

“Transplantation is one critical area of medicine that requires the use of immunosuppressants. Cannabinoids have emerged as powerful drug candidates for the treatment of inflammatory and autoimmune diseases due to their immunosuppressive properties. Cannabinoids are the tetrophenolic compounds found in the plant, Cannabis sativa.” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2923447/