In an unprecedented move that will certainly change the sport of MMA in the United States (how much, time will tell), the Nevada State Athletic Commission will begin randomly drug testing licensed fighters.
Nevada adds random drug tests for fighters - MMA - Yahoo! Sports
One of the major criticisms of MMA have been the fact that before, fighters were only tested on the day of their fights. So it took a fool to fail the tests since they knew when they would be administered.
Now, the random drug tests will occur at any time of the year and all fighters are eligible to be tested (all who are licensed in Nevada).