The leaves and flowering parts of the (cannabis indica) and (cannabis sativa) plants, commonly known as marijuana, have been used for thousands of years for a variety of purposes ranging from recreational drug to medicinal analgesic to religious sacrament. The term cannabinoid refers to chemicals found exclusively in these cannabis plants. Although there are 70 known cannabinoids found in marijuana, the chemical delta-9-tetrahydrocannabinol (THC) has been identified as the principal psychoactive and pharmacologically significant component.

There is a rich history concerning the medicinal use of marijuana and THC as pain killers. Archeological findings at an ancient site in Jerusalem suggest that marijuana was consumed to alleviate labor pains 1,600 years ago. Upon its introduction to the United Kingdom and United States in the 1800s, marijuana was reportedly used to treat a number of ailments including tetanus, migraine, depression, gonorrhea, and opium addiction with varying results. It is rumored that...