Mike Tyson has long been an advocate of marijuana use, even for athletes. But there is one other drug he used to take at the back end of his prime.

The heavyweight champ revealed on “The Katie Miller Podcast” that he took fentanyl “quite a few times” during the late ’90s.

“It was a painkiller, and I used to use it to patch up my toe,” Tyson said.

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The effects of the drug got to the boxer quite quickly, and quitting was apparently difficult.

“It was like heroin — once it wears off and you take the Band-Aid off, you start withdrawing, throwing up, just like if you were on heroin,” Tyson said.

But Tyson had no choice but to stop.

“It was illegal if it [was] caught in my bloodstream. It was a narcotic, my friend told me. It was brand new. I told my friend ‘could I use this?’ No one ever heard of it,” Tyson said.

On the podcast, Tyson again called for the use of marijuana, particularly for athletes.

“It’s not a drug. It’s medicine,” Tyson said.

Boxer Mike Tyson of the United States (top right) exhorts Andrew Golota of Poland (not pictured) to continue fighting as referee Frank Garza Jr. raises his hand to award a TKO after Golota refused to answer the bell for the third round of their fight at the Palace of Auburn Hills in Michigan on Oct. 20, 2000. (DANIEL LIPPITT/AFP via Getty Images)

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Tyson added that athletes “play better” when they smoke, and said he wishes he had smoked during his fighting days.

Tyson told Fox News Digital in an exclusive interview on June 30, his 59th birthday, that whether he fights again will depend on whether cannabis is legalized and rescheduled. 

He led a coalition of current and former athletes, including Kevin Durant, Dez Bryant and Antonio Brown, who signed a letter to the White House in late June, lobbying for federal cannabis reform. The letter called for the rescheduling of cannabis from Schedule I to Schedule III, clemency for “nonviolent” marijuana offenses, and ending “discriminatory banking practices,” related to financial regulations of the cannabis industry. 

Mike Tyson and Jake Paul are separated as they face off during their ceremonial weigh-in at The Pavilion at Toyota Music Factory on November 14, 2024 in Irving, Texas. The two are scheduled to meet in a heavyweight bout on November 15 at AT&T Stadium in Arlington, Texas.  (Christian Petersen/Getty Images)

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Tyson told Fox News Digital in the June 30 interview that rescheduling was the “most important” goal in his letter. He added that he was “let down” by how former Presidents Barack Obama and Joe Biden handled federal marijuana reform, but is hopeful that Trump will take a new approach. 

Fox News’ Jackson Thompson contributed to this report.

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