I have heard too many stories of patients with debilitating symptoms being ostracized by their doctors when asking about the therapeutic benefits of cannabis.
Here is a comprehensive scholarly article on the National Institute of Health website about the immense therapeutic possibility of cannabis on diseases and ailments such as Alzheimers, PTSD, pain and epilepsy. It also details the potential harms, including addiction. Have your doctor read this in depth report before he or she makes a conclusion about cannabis.
As an objective comparison, ask your doctor to provide similar data on the conventional pharmaceuticals for your ailments. What are their harms and benefits? Then you and your doctor can decide what is a better and safer treatment for disease, symptoms, or the side effects of other medications.