Chris Cornell's widow, Vicky Cornell, has alleged Dr. Robert Koblin and his Beverly Hills office "negligently and repeatedly" prescribed the late singer - who took his own life last year aged 52 - "dangerous mind-altering controlled substances".
In a lawsuit filed at the Los Angeles Superior Court, she claims such substances "clouded his judgement, and caused him to engage in dangerous impulsive behaviours that he was unable to control, costing him his life".
According to the document, which has been obtained by TMZ, Vicky alleges the doctor prescribed Chris large amounts of anti-anxiety drug Lorazepam, which is also known as Ativan, during the last 20 months of his life, without examining the Soundgarden frontman.
Vicky is said to be suing the doctor for unspecified damages.
Chris was founded dead in his Detroit hotel room in May 2017 and his death was ruled as suicide.
Toxicology reports found traces of several drugs in his system, but a coroner's report said the drugs were not the cause of the 'You Know My Name' hitmaker's death.
This comes just a month after unveiled a statue in his honour at Seattle's MoPOP Museum, and Vicky hailed her late husband as the "voice of a generation".
She said: "He was the voice of a generation, and an artist that continues to draw us closer together, forever.
"I thank you for embracing and loving Chris so deeply. Thank you, Seattle, for the support and loudest love."
Vicky herself had commissioned the statue and said it was her gift to "the tight-knit community that gave him his start."