Why do people oppose the use of marijuana for medical purposes?

Unreliable drug: It's a very unpredictable drug. The same person at different time can experience euphoria, relaxation or extreme paranoia, panic and hallucinations at a different time. Dosage and consistency can't be measured as there are dozens of active compounds in the drug. Differences with generic meds are nothing compared to differences with mj. Pot is so potent addiction, withdrawal and dependence occur.