'Can't Buy Me Love' Star Cause of Death Massive Overdose

9/2/2015 3:25 PM PDT BY TMZ STAFF
EXCLUSIVE

0902-amanda-peterson-GETTY-01Amanda Peterson -- who starred in "Can't Buy Me Love" died from an accidental overdose of a deadly combination of drugs.

The 43-year-old disappeared just before the 4th of July and her body was found on July 5th.

According to the Weld County Coroner in Colorado, Peterson had a variety of prescription drugs in her system, including benzodizepines (anti-anxiety meds), opiates and phenothiazines (an anti-psychotic medication).  She also had marijuana in her system. 

One of the drugs in her system -- Gabapentin -- was prescribed for pain and the medical examiner said she had 6 times the normal level in her system. 

The report says Peterson was "naive to opiates." 

The toxicology report says a week before her death she told someone she ingested  morphine medication she got from friends. The reports says she was self-medicating to control pain.

As for why she died, the report says it was because of a "morphine effect" ... which causes respiratory failure.

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