Did Prince die of an overdose?

Prince's final days and unexpected death at age 57 raise questions among experts familiar with prescription painkiller overdoses. It's possible the innovative musician's demise represents one of the most public tragedies in an overdose crisis now gripping America.

A law enforcement official told The Associated Press on Thursday that investigators are looking into whether Prince died from an overdose and whether a doctor was prescribing him drugs in the weeks before he was found dead at his home in suburban Minneapolis. The law enforcement official has been briefed on the investigation and spoke to the AP on condition of anonymity because he was not authorized to speak to the media.

Whether Prince was addicted to painkillers is uncertain, but some are wondering whether the stigma surrounding addiction may have prevented Prince - who built a reputation as a sober superstar - from seeking help if he was becoming dependent.

With good management and no history of addiction, opioids can help people find relief from pain with only a small risk of causing addiction, according to a 2010 systematic review of the available studies.

"If you do not have a past history of addiction and are in your 40s and getting pain treatment with opioids, your odds of becoming newly addicted are low," said Maia Szalavitz, author of "Unbroken Brain," a newly published book about addiction. "One study of thousands of ER visits for overdose found that only 13 percent of victims had a chronic pain diagnosis."

If Prince had become addicted, Szalavitz said, he may have shunned seeking help.

"The stigma that is associated with addiction could well have been what killed him," she said. "Maybe he was afraid to seek help. Maybe he sought help before and was treated in a disrespectful and unproductive way."