Cannabis and Cannabinoids (PDQ®) - National Cancer Institute General Information Cannabis, also known as marijuana, originated in Central Asia but is grown worldwide today. In the United States, it is a controlled substance and is classified as a Schedule I agent (a drug with increased potential for abuse and no known medical use). The Cannabis plant produces a resin containing psychoactive compounds called cannabinoids. The highest concentration of cannabinoids is found in the female flowers of the plant. As a botanical, Cannabis is difficult to study because of the lack of standardization of the botanical product due to the many climates and environments in which it is grown. Clinical trials conducted on medicinal Cannabis are limited. The potential benefits of medicinal Cannabis for people living with cancer include antiemetic effects, appetite stimulation, pain relief, and improved sleep. In the practice of integrative oncology, the health care provider may recommend medicinal Cannabis not only for symptom management but also for its possible direct antitumor effect. Cannabinoids are a group of terpenophenolic compounds found in Cannabis species (Cannabis sativa L. and Cannabis indica Lam.). This summary will review the role of Cannabis and the cannabinoids in the treatment of people with cancer and disease-related or treatment-related side effects.