Lil Peep[1]'s mom says his management team and the company primarily responsible for his final tour supplied the rapper with drugs, an unstable environment and pushed him to the point of exhaustion ... all factors that led to his tragic death.

Peep's mom, Liza Womack, filed a lawsuit Monday against First Access Entertainment and people associated with the company. Womack claims, starting in 2017 during Peep's The Peep Show tour, the use of controlled drugs and illegal substances were allowed, normalized and even encouraged by management.

Womack says during a stop in London, her son was gifted a bottle of pills by one of his managers during a group dinner.

The docs claim the rampant drug use continued during Peep's final Come Over When You're Sober tour. Womack says Peep was regularly supplied with Xanax, Ketamine and other drugs throughout the tour.

Womack alleges at one point, Peep expressed to management he wanted to quit the tour, saying he was physically and emotionally drained ... but they ignored his pleas and made him continue on the road.

They say this behavior and lack of regard for Peep's well-being ultimately led to his overdose in November 2017, when he was found dead[2] on his tour bus. Peep's cause of death was listed as a combination[3] of fentanyl and a brand of Xanax.

Womack is suing for unspecified damages.

We reached out to First Access Entertainment ... so far, no word back.

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