Norboletone (INNTooltip International Nonproprietary Name) (former proposed brand name Genabol), or norbolethone, is a synthetic and orally active anabolic–androgenic steroid (AAS) which was never marketed.

[1] It was first developed in 1966 by Wyeth Laboratories and was investigated for use as an agent to encourage weight gain and for the treatment of short stature, but was never marketed commercially because of fears that it might be toxic.

[3] Norboletone was found to have been brought to the market by the chemist Patrick Arnold, of the Bay Area Laboratory Co-operative (BALCO), an American nutritional supplement company.

[4][5] In 2002, Don Catlin, the founder and then-director of the UCLA Olympic Analytical Lab, identified norboletone for the first time in an athlete's urine sample.

[6] Norboletone is on the World Anti-Doping Agency's list of prohibited substances,[7] and is therefore banned from use in most major sports.