Amendment 20, approved by Colorado voters in November 2000, authorizes the use of marijuana to alleviate certain debilitating medical conditions:  cancer, glaucoma, HIV/AIDS positive, cachexia; severe pain; severe nausea; seizures, including those that are characteristic of epilepsy; or persistent muscle spasms, including those that are characteristic of multiple sclerosis. In addition, patients and physicians may submit petitions to the Colorado Department of Public Health and Environment to include other medical conditions that may be alleviated by the medical use of marijuana. 

Amendment 20 authorizes a patient or a primary caregiver who has been issued a Medical Marijuana Registry identification card to possess no more than two ounces of a usable form of marijuana and not more than six marijuana plants, with three or fewer being mature, flowering plants that are producing a usable form of marijuana.

For answers to specific questions, contact your doctor or visit the Colorado Medicinal Marijuana Registry's website: http://www.cdphe.state.co.us/hs/medicalmarijuana/marijuanafactsheet.html