The 57-year-old star’s death was an “accident” caused by self-diagnosed fetanyl, a powerful opioid used to treat pain, the medial examiner’s office in his native Minnesota said in a statement.
The medical examiner gave few other details, with the sheriff’s department in Minnesota’s Carver County still investigating.
The examiner’s office said that the sprightly five-foot-two (1.6-meter) “Purple Rain” star weighed just 112 pounds (51 kilograms) and listed the resting spot of his ashes as unknown.
Fentanyl, a synthetic opiate, is more powerful than morphine and is used to treat people with chronic pain. It is only available by prescription.
The 57-year-old “Purple Rain” star was found dead at his Paisley Park estate outside Minneapolis on April 21, days after his plane made an emergency landing that was also reportedly due to a painkiller overdose.
A California doctor who treats painkiller addiction, Howard Kornfeld, had been urgently making plans to treat Prince when the artist died, the specialist’s lawyer said last month.
Kornfeld’s son Andrew had arrived at Paisley Park to explain the treatment to Prince when he discovered his lifeless body and called the 911 emergency line for help.
Prince had appeared to be healthy to the public and was famous for his marathon performances in which he would play for hours or put on two shows in a night.
But Prince underwent hip surgery in 2010 and was famously private about his personal life.