Kiwi rugby league players will have to accept new drug testing procedures if they want to play for New Zealand in the upcoming ANZAC test against Australia.
The NZRL is to follow the NRL's lead and implement a testing procedure for prescription drugs.
At the world cup last year Kiwis players mixed sleeping pills with alcohol and energy drinks, producing a high without falling foul of anti-doping rules.
The NRL says it will gather the test results this year to see how widespread the problem is, with the likelihood penalties will be introduced from next year.
The NZRL's high performance manager Tony Iro says the addition to the code of conduct means they could suspend playes even though the drugs aren't illegal.
Iro says he will be outlining the problems the sport has experienced with the issue at a meeting of national sports organisations over the weekend.