Investigators believe a health scare about a week before Prince's death, which caused an unscheduled landing of his plane in Illinois, was likely the result of a reaction to the pain medication.
Officials say Prince was treated for a potential overdose of pain medication.
But United States toxicology specialist Dr Drew Pinsky says Prince's death may have been caused by a combination of pills.
“It’s only when you add in sleeping medication or anxiety medication that the combination is lethal. It’s a very common and dangerous combination.”
