voiced support for the medical use of cannabis in professional sports. Dr. Sanjay Gupta, neurosurgeon and chief medical correspondent for CNN, has produced a five-part documentary series for the network – titled Weed – arguing in favor of the medical benefits of cannabis. Gupta was initially dismissive toward the medical use of cannabis, but upon researching further he changed his mind and wrote a column apologizing for his past views. Filmmaker Jed Riffe has also explored the subject in his 2006 documentary Waiting to Inhale. Opposition The American Academy of Pediatrics and American Psychiatric Association oppose the legalization of medical cannabis outside the FDA approval process. However, the AAP also supports rescheduling for the purpose of facilitating research. Individuals who have been particularly active in opposing the medical use of cannabis include Barry McCaffrey, John Walters, Andrea Barthwell, Bill Montgomery, Mark Souder, Sheldon Adelson, Mel Sembler, and Kevin Sabet. Former U.S. Rep. Bob Barr was a particularly ardent opponent of medical cannabis in Congress, introducing the "Barr amendment" which blocked implementation of a Washington, D.C. ballot initiative legalizing the medical use of cannabis. After leaving Congress, however, Barr renounced his earlier views and joined Marijuana Policy Project to lobby for repeal of the legislation he originally authored. Other The American Medical Association and American College of Physicians do not take a position on the legalization of medical cannabis, but have called for the Schedule I classification to be reviewed. The American Academy of Family Physicians and American Society of Addiction Medicine also do not take a position, but do support rescheduling to better facilitate research. The American Heart Association supports rescheduling to allow for "a more nuanced approach to marijuana legislation and regulation". The American Cancer Society and American Psychological Association have noted the obstacles that exist for conducting research on cannabis, and have called on the federal government to better enable scientific study of the drug. Cannabinoid drugs There are currently four cannabinoid drugs (Marinol, Syndros, Cesamet, and Epidiolex) available for prescription use in the United States. For non-prescription use, CBD derived from hemp is legal at the federal level but legality (and enforcement) varies by state. Dronabinol Dronabinol is synthetically manufactured THC. It has been approved by the FDA in pill form as Marinol and in oral solution form as Syndros. Marinol Marinol is a sesame oil suspension of dronabinol encapsulated in a gelatin shell. It received FDA