Tom Petty — How A Drug Blunder Killed The Legendary Rocker

Tom Petty went to his grave in what experts told The National ENQUIRER may have been a medical mistake!

A shocking autopsy report revealed Tom had died with a slew of drugs in his system, including oxycodone and a troubling mix of Fentanyl and generic Xanax. The ENQUIRER also learned the “Free Fallin’” singer received regular injections of Decadron, a powerful anti-inflammatory used to ease severe pain — without consulting a doctor!

“The doctor said to never give Tom a shot of Decadron unless he was called first,” an insider spilled to The ENQUIRER. Dr. Gabe Mirkin, a longevity specialist who did not treat Tom, told The ENQUIRER: “Decadron in large doses can cause blood clots — which may lead to fatal heart episodes!”

The 66-year-old Petty launched a 40th anniversary tour with The Heartbreakers on April 20, and did more than 50 dates in the U.S., Canada and London before their final gig on Sept. 25 at the Hollywood Bowl.

With the grueling pace, he felt he desperately needed B-12 shots and Decadron to perform, insiders said. “Back in the ’90s, Tom had a bad heroin habit that left him with muscle and bone pain,” tattled a source.

“His family begged him to rest, but he vowed to finish the tour.” When the tour ended, Tom was in a state of virtual collapse — and died Oct. 2 after suffering cardiac arrest.