As usual in the United States, the Nevada Athletic Commission carried out anti-doping and anti-drug tests on the fighters who participated in WEC-33, on April 3, and according to the Commission, all results were negative.
The athletes who participated in the exams were: Doug Marshall, Brian Stann, Chael Sonnen, Bryan Baker, Rich Crunkilton, Marcus Hicks, Logan Clark, Steve Cantwell, and Alex Serdyokov