Irvin who was defeated at UFN 14 by Silva took a post fight urinalysis and it came out that he had tested positive for methadone and oxymorphone which are non approved pain medications. Irvin had this to say in his letter to the NSAC, “In the days leading up to my fight with Anderson Silva, I experienced some residual pain in my foot from a previous injury,” wrote Irvin in an Aug. 14 letter. “I made the extremely poor choice to take some pain medications that I did not have a prescription for. I realize this was an ignorant and dangerous decision.”
When Chuck Liddell pulled out of his match with Rashad Evans at UFC 85 it was Irvin who stepped in to replace Liddell and face Evans, but had to pull out with the foot injury that has caused him to make the decision to take the banned medications.
At the moment Irvin who was temporarily suspended until August 12 due to a separate pending disciplinary hearing is planning on meeting with the commission in person. Irvin could possibly be out of action for 6 to 12 months and pay a percentage/fine out of his salary for his bout with Anderson Silva. We will keep you up to date when the NSAC makes a ruling on Irvin.
Source - Sherdog.com