"I talked to some teams, and I told them I had smoked marijuana before," Burfict said. "It's not like I'm the only person that has ever done that."
Burfict said he no longer uses the drug.
NFL Network contributor and Fox Sports insider Jay Glazer reported earlier Wednesday that NFL teams were informed this week the Arizona State linebacker had failed a drug test. But Burfict said league officials haven't notified him of that.
"Nobody told me anything from the NFL," Burfict said. "I don't want to talk about it too much."
Burfict was an All-American as a sophomore, but his performance declined last season. At the NFL Scouting Combine in February, he ran a sluggish 40-yard dash -- a high 4.9- to 5.0-second clocking that he improved to 4.79 to 4.85 seconds at his March pro day. He also reportedly struggled during interviews.
NFL Network draft analyst Mike Mayock has criticized Burfict throughout the draft process, recently predicting the linebacker might go undrafted.
"That's his job," Burfict said of Mayock's criticism. "He has to have something to talk about. Mike Mayock doesn't know me, he's never interviewed me. I have a lot of respect for Mayock. I don't know why he has no respect for me. I'm a human being. I'm not letting it get to me."
If he could talk to Mayock, Burfict said he would ask: "Why is he being so hurtful to a young man and trying to trash me? I think about what he said with every rep that I do in the weight room. I use the criticism as motivation, but I like Mayock. I have a lot of respect for him. I would just ask him to be fair."