Matthew Perry and his assistant Kenny Iwamasa spent at least $US55,000 ($A82,000) on ketamine in the 29 days before the actor's death.
The Friends star died in October 2023 at the age of 54 after suffering an overdose of the drug and 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.
According to Us Weekly, court documents filed as part of a criminal case against Iwamasa, 59, reveal the actor and his assistant spent a minimum of $US55,000 on the tranquilliser in less than a month.
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 of injections that took place 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 the actor with the drug three times on the day of his death, which was attributed to drowning in the hot tub at his Pacific Palisades mansion and the “acute effects” ketamine.
Four other people - including two doctors - have been arrested and charged in connection with supplying the drugs that killed the actor.
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 in a statement to Entertainment Weekly.
"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.
"Every day, the DEA works tirelessly with our federal, state, and local partners to protect the public and to hold accountable those that distribute deadly and dangerous drugs, whether they are local drug traffickers or doctors who violate their sworn oath to care for patients."
