Source: Cannabinoids for treatment of chronic non-cancer pain; a systematic review of randomized trials.
The authors of this fantastic 2011 review took a look at the use of cannabinoids for different types of chronic pain such as neuropathic pain, rheumatoid arthritis, and fibromyalgia. They called the quality of all of the reviewed trials "excellent" and found "no serious adverse effects." Cannabinoids were able to provide pain relief and improve quality of sleep, which is important because many people who deal with chronic pain report that it has a very negative impact on their sleep.
