Why are THC and cannabis banned but not CBD?

In 2017, WADA removed CBD but not other cannabinoids from its list of prohibited substances. The rule change did not take effect until January 1, 2018, which gave athletes little time to start incorporating CBD into their regimes for the Winter Olympics in Pyeongchang the same year.

Without specifying the reason, WADA states: “All natural and synthetic cannabinoids are prohibited except for cannabidiol (CBD).