Cowboys defensive lineman David Irving lambasted the NFL’s drug policy Thursday night on Instagram Live.

Irving, who was suspended indefinitely for violating that policy, aired his grievances on a roughly 20-minute video. He appeared to smoke marijuana while streaming. He said he is leaving the league.

“Basically guys, I quit,” Irving said. “There’s a lot of (expletive) (expletive) up with the league.”

Irving described the marijuana as “this medicine right here,” arguing that the league should support him treating pain and mental illness with marijuana in place of opioids. Irving said he’d seen the addictive dangers of opioids while in treatment facilities; he prefers the natural plant to treat challenges including injuries and ADHD.

“If I’m going to be addicted to something, I’d rather it be marijuana, which is medical,” Irving continued. “I do not consider it a drug, rather than the Xanax bars or the hydro[codone] or the Seroquel and all that crazy (expletive) that they feed you. Like I said, it ain’t about smoking weed.

“How many NBA players you see get in trouble about this? How many coaches you see get in trouble about this? How many baseball players get in trouble? UFC players getting in trouble? How many actors?”

The Kansas City Chiefs signed Irving as an undrafted free agent out of Iowa State in 2015. The Cowboys poached him from Kansas City’s practice squad that September and re-signed him to one-year deals each of the last two offseasons.

In 2017 and 2018, Irving notched eight sacks, 12 quarterback hits and 26 tackles. He deflected six passes in 2017, too, setting up game-sealing interceptions for teammates. He forced a fumble. He was effective when on the field.

But he was often unavailable, starting each of the last two seasons with four-game drug suspensions. In 2017, he violated the league’s policy on performance-enhancing drugs. The next year, his suspension came through the league’s substance-abuse policy. Last Friday, Irving received a third suspension for violating the substance-abuse policy.

Irving said the stringent policy was enough to make him quit.

“I love football, don’t get me wrong,” he explained. “However, I don’t love the NFL.”

Irving cited medical benefits of marijuana and said he’d consider playing in the NFL again if the next collective bargaining agreement (the current one is set to expire after the 2020 season) loosens marijuana policies in line with other professional leagues’. Irving wanted to serve as the Cowboys’ NFL Players Association representative on these issues in 2018 but was not selected.

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Irving was rarely at practice and meetings in 2018 even after returning from suspension. A high-ankle sprain and custody battle for his daughter Zoe, who was on his Instagram earlier Thursday night, were among issues that kept him off the field. Dallas carried Irving on its 53-man roster all season even though he played just two games, both in October.

Irving is set to become an unrestricted free agent on Wednesday when the league year turns over. He is suspended. The Cowboys have said they do not plan to re-sign him.

“[David] really was not part of our team last year,” head coach Jason Garrett said last week at the combine. “He’s a free agent as we know it.”

Garrett did voice strong support for defensive end Randy Gregory, who also received another indefinite suspension last week for violating the league’s substance-abuse policy. Garrett said the team will support Gregory as he seeks professional help, noting that “sometimes, relapse is part of rehab.”

Irving said he’s at peace with quitting football and will find other outlets to support himself and 6-year-old Zoe. That’s the price he said he’s willing to pay to self-medicate with weed.

“Plants over pills,” Irving said. “I don’t want to be (expletive) braindead when I’m 50.”

Follow USA TODAY Sports' Jori Epstein on Twitter @JoriEpstein.

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