Does anyone use marijuana for medical purposes?

I see a pain specialist who prescribes heavy narcotics for the past 7 years. As time went on the doses went up.(not what I wanted and no you don't get any "buzz" from it because the pain eats it up !!) So I tried pot and the pain actually subsided too a certain degree. My delema is do I risk asking the doctor for medical pot and have him alianate me? I can't afford to lose this doctor they are very hard to find. What do you think I should do?