Matthew Perry and his assistant Kenny Iwamasa spent at least $US55,000 ($82,000) on ketamine in the 29 days before the actor’s death, it has been revealed.

The Friends star died in October 2023 at the age of 54 after suffering an overdose of the drug.

Court documents reveal the TV star and his live-in helper spent thousands purchasing 55 ketamine vials and injections in the weeks leading up to the tragedy.

Perry had reportedly been receiving ketamine treatments from his regular doctor to treat depression, but wanted to get more than he had been prescribed.

According to Us Weekly, court documents filed as part of a criminal case against Iwamasa, 59, reveal he and Perry spent at least $US55,000 on the tranquilliser in less than a month.

The paperwork also reveals that Perry asked his assistant to “shoot him up with a big one” on the day he died.

Iwamasa has pleaded guilty to one count of conspiracy to distribute ketamine causing death and faces up to 15 years in prison.

The outlet reports the documents state Perry and Iwamasa met a doctor in a car park for injections that were done in the back of a car.

They also suggest Iwamasa handed over thousands of dollars in cash to get hold of bottles of ketamine, allegedly spending $US6000 on 25 vials just nine days after he purchased 25 bottles.

Court documents filed as part of Iwamasa’s plea agreement previously revealed he injected Perry with ketamine three times on the day of his death.

An autopsy found the star’s death was due to drowning in the hot tub at his Pacific Palisades mansion and the “acute effects” of ketamine.

Four other people – including two doctors – were also arrested last week and charged in connection with supplying the drugs that killed Perry.

One of the doctors, Salvador Plasencia is said have texted “I wonder how much this moron will pay” in a 2023 message.

Prosecutors allege that Perry sometimes paid $2000 for a vial that had cost another of the doctors, Mark Chavez, $12.

Perry’s stepfather – Dateline presenter Keith Morrison – has since thanked authorities for taking the case “seriously”.

“We were and still are heartbroken by Matthew’s death, but it has helped to know law enforcement has taken his case very seriously,” he said.

“We look forward to justice taking its course and we’re grateful for the exceptional work of the multiple agencies whose agents investigated Matthew’s death. We’re hoping unscrupulous suppliers of dangerous drugs will get the message.”

DEA administrator Anne Milgram said of the case: “Matthew Perry’s journey began with unscrupulous doctors who abused their position of trust because they saw him as a payday, to street dealers who gave him ketamine in unmarked vials.”

She said the DEA worked tirelessly every day to protect the public and hold accountable those who dealt in deadly and dangerous drugs – “whether they are local drug traffickers or doctors who violate their sworn oath to care for patients”.

-with AAP