Medical cannabis, or medical marijuana, refers to the use of cannabis and its cannabinoids to treat disease or improve symptoms. The use of cannabis as a medicine has not been rigorously scientifically tested, often due to production restrictions. There is limited evidence suggesting cannabis can be used to reduce nausea and vomiting during chemotherapy, to improve appetite in people with HIV/AIDS, and to treat chronic pain and muscle spasms. Its use for other medical applications is insufficient for conclusions about safety or efficacy.