Of course she used it for medical reasons. The singer admits it helped her with the horrible side effects of chemo during her fight against breast cancer. She tells Dateline:
"Instead of taking five or six of the prescriptions, I decided to go a natural route and smoke marijuana." She also said all the Doctors told her it was the "best help for the effects of chemotherapy."
Hey, whatever it takes to get through that and be cancer free - You go girl!