Former National Football League quarterback Johnny Manziel reveals in a new documentary his drug usage during his playing career and a suicide attempt following his release from the Cleveland Browns in 2016.

In Netflix's upcoming documentary "Untold: Johnny Football," Manziel -- who became the first redshirt freshman to win the Heisman Trophy while playing at Texas A&M in 2012 -- said that he began using OxyContin and cocaine every day following the 2015 season, which led to his weight dropping from 215 pounds that January to 175 pounds in September.

Poor play and legal troubles soon followed Manziel. A Texas grand jury indicted Manziel on a misdemeanor assault charge of his former girlfriend, Colleen Crowley. Manziel denied hitting Crowley at the time and the charges were later dropped after he met the court's terms for a dismissal agreement.

The Browns would release Manziel in March 2016, which he said he was later diagnosed with bipolar disorder.

Manziel said he refused to enter rehab twice and began "self-sabotaging," going on a "$5 million bender" before attempting suicide.

"I had planned to do everything I wanted to do at that point in my life, spend as much money as I possibly could and then my plan was to take my life," Manziel said in the documentary. "I wanted to get as bad as humanly possible to where it made sense, and it made it seem like an excuse and an out for me."

Manziel said he had purchased a gun "months earlier" with the intention to use it for suicide but the gun "malfunctioned" when he pulled the trigger.

"Still to this day, don't know what happened. But the gun just clicked on me," he said.

Manziel's relationship with his family at the time was "strained" due to his refusal to seek treatment, he said. Manziel later returned to his family's home in Texas after leaving Los Angeles following the suicide attempt.

"It's been a long, long road, and I don't know if it's been great or if it's been bad -- that's kind of still up for debate," Paul Manziel, his father, said in the documentary. "But we're blessed. And he's still with us. And we can mend all the fences still. I think Johnny's got a lot better days coming than what he's had."

CNN has reached out to the Browns for comment.

Manziel was drafted in the first round of the 2014 NFL Draft. Following his release from the Browns, Manziel played for multiple teams in the Canadian Football League (CFL) and in the now-defunct Alliance of American Football (AAF). Manziel last played in the Fan Controlled Football league.

The Netflix documentary is scheduled to be released on Tuesday.