Dr. Michael Miller, a recent Wisconsin Medical Society officer and past president of the American Society of Addiction Medicine, said marijuana can be addictive, isn’t better than approved drugs and is unpredictable because purity and potency vary. Dr. Angela Janis, director of psychiatric services at UW-Madison’s University Health Services … said research has found considerable benefit in adults for pain, nausea and muscle spasms, and some studies suggest help for sleep disorders and neurological conditions such as Parkinson’s disease.