A Coala-T-Cannabis Survey Study of breast cancer patients' use of cannabis before, during, and after treatment.

Almost half of patients with breast cancer use cannabis, most commonly during active treatment to manage common symptoms and side effects: pain, anxiety, insomnia, and nausea. However, most patients do not discuss cannabis use with their physicians. Instead, the internet and family/friends are the most common sources of cannabis information. Furthermore, most participants believe that cannabis products are safe and are unaware that the safety of many products is untested.