img source: The Guardian
The drug in question? Percocet. It is commonly prescribed in pill form and made up of one part over-the-counter-style pain killer, like Tylenol, and another part oxycodone — a powerful opioid pain-killing sedative that has its own history of inducing fatal overdoses. This prescription drug is very well known, especially around Minnesota, where Prince had resided for the majority of his 57 years.
During a conference, one speaker noted that Prince’s addiction to opioids started innocently enough after a dentist prescribed such opioids following a "minor dental procedure," the Minneapolis Star-Tribune reported at the time.
Prince’s recent visit to the hospital possibly suggests the use of an antagonist shot (“save shot”) to recover from his “illness.” A doctor told Hollywood Life that this alleged episode points to evidence that Prince was dependent on prescription drugs. Then, his death four or five days later suggests he may have used the drug again. – An overdose. Dr. Deni Carise, chief clinical officer of Recovery Centers of America, said during an exclusive interview with Hollywood Life.
In this context, it is highly likely that Prince was addicted to opioids, such as heroin or prescription drugs like Percocet, Vicodin or OxyContin.