Name the cause and type of pain, and chances are that recent double-blind research and/or decades of anecdotal information form patients show that medical marijuana provides effective relief. This included chronic pain resulting from severe injuries and conditions, as specified below. Where pain is connected to inflammation , research has found that medical marijuana delivers site-specific anti-inflammatory relief. Most patients report that marijuana doesn't reduce their ability to function normally the way opiates do, and that they can reduce dramatically or even eliminate their need for opiates and similar risky pain-relievers when using marijuana.