Cornell's widow, Vicky Cornell, and their children, Toni and Christopher, are plaintiffs in the lawsuit filed in Los Angeles Superior Court alleging that prescription drugs, especially the anti-anxiety drug Lorazepam, led to erratic behaviour from the Soundgarden frontman.

Cornell died in Detroit in 2017 aged 52.

The lawsuit says Dr Robert Koblin and his Beverly Hills office "negligently and repeatedly" prescribed "dangerous mind-altering controlled substances to Chris Cornell which impaired Mr Cornell's cognition, clouded his judgment, and caused him to engage in dangerous impulsive behaviours that he was unable to control, costing him his life".

It focuses in particular on Dr Koblin's prescribing Cornell large amounts of Lorazepam, which is sold under the brand name Ativan, to Cornell in the 20 months leading up to his death.

Coroner's investigators ruled Cornell's death a suicide by hanging.

Toxicology tests showed the presence of Ativan along with barbiturates, caffeine, the anti-opioid drug naloxone, and a decongestant.

But the post-mortem report said the drugs were not a cause of death.

The lawsuit says the doctor knew that Cornell had a serious history of substance abuse, and he failed to examine or consult with him as he was prescribing the drugs.

The "unmonitored use of such excessive amounts of Lorazepam ... was known to increase the risk of suicide because it can severely impair judgment, thinking and impulse control and diminish the ability of a patient to think and act rationally", the lawsuit says.

Staff at Dr Koblin's office said there was no immediate comment.

Australian Associated Press