Medical marijuana helps cancer patients in ways that pharmaceuticals can't, it serves many great purposes. One of them is that it helps you regain your appetite, helps manage pain, and relieves nausea and vomiting. It also improves sleep in patients using chemotherapy. Marijuana slows down and prevents cancer cells from spreading throughout the body. Another way it is useful is in patients with post-traumatic stress disorder (PTSD), because it helps promote memory extinction. Memory extinction is the normal healthy process of removing the association of harmful stimuli. This way it helps to control the brain from fear and anxiety of what may have affected them. Multiple sclerosis is another medical condition on which marijuana has positive effects. It is used to stop the negative neurological muscle spasms caused by the disease. THC in marijuana binds to receptors in muscles and nerves to relieve pain. Arthritis is another common medical condition that can be easily controlled using medical marijuana. Marijuana helps reduce pain, inflammation, and also helps promote sleep, which in return can help relieve discomfort associated with rheumatoid.