There are at least two major active chemicals in marijuana that researchers think have medicinal applications (there are up to 79 known active compounds). Those two are cannabidiol (CBD) — which seems to impact the brain mostly without a high— and tetrahydrocannabinol (THC) — which has pain relieving (and other) properties.
Proposition 203, the Arizona Medical Marijuana Act, protects patients from Medical Marijuana Doctors in Arizona prosecution for using limited amounts of marijuana on their doctor’s recommendation. Qualifying patients who register with the Arizona Department of Health Services will obtain marijuana from nonprofit medical marijuana dispensaries and caregivers regulated by the Arizona Department of Health Services…
According to the NASEM report, studies show that both inhaled marijuana (vaporized or smoked) and cannabinoid compounds that come from the cannabis plant (like THC, mostly responsible for the high, or cannabidiol, CBD, one of the most medically promising of the hundreds of chemical compounds found in marijuana) work for pain.