'Can't Buy Me Love' Star Amanda Peterson Died From Acute Morphine Toxicity, Coroner Says

— -- "Can't Buy Me Love" star Amanda Peterson died from acute morphine toxicity, according to autopsy results from the Weld County Coroner in Colorado obtained by ABC News today.

The 43-year-old actress died in July, her mother told ABC News at the time. The former actress' mother, Sylvia, said her daughter's death was "unexpected" and a "big blow."

Peterson had marijuana and multiple prescription drugs in her system at the time of her death, according to the coroner's pathology reports. Specifically, she had six times the normal levels of Gabapentin in her system, which is an anti-epileptic medication, according to Webmd.com. It may also be used to treat pain.

Peterson's death is being ruled accidental, the coroner's report added, noting that "for unclear reasons it appears that the decedent was attempting to self-medicate her pain at the time of death."

Peterson had been prescribed multiple medications for lung and heart disease, according to the Associated Press.

The actress, who was found dead in an apartment complex on July 5, is best known for playing popular high school student Cindy Mancini in the 1987 film, "Can't Buy Me Love."