Stephan Bonnar’s Death Was Due To Fentanyl Overdose

The cause of 45-year-old UFC hall-of-famer Stephan Bonnar’s death has finally been revealed as an accidental Fentanyl overdose.

When he first died on December 22nd of last year the exact cause wasn’t clear, with the UFC reporting at the time that it had been due to, “presumed heart complications while at work,” but the real cause has since emerged via an official report from the Nevada Clark County Coroner.

Bonnar had retired from MMA in 2014 after a split-decision loss to Tito Ortiz in the Bellator promotion, and his later years would be marred by struggles with injuries, drug and alcohol abuse.

In 2018, Bonnar was arrested in Nevada and charged with a DUI offense after driving recklessly, with bodycam footage showing that he was heavily intoxicated and incoherent.

In 2021, self-filmed footage of Bonnar causing a commotion at the E.R. department of a hospital went viral.

Bonnar later explained that he’d suffered a bad back injury during a pro-wrestling match and had gone on to contract a staph infection too, and had gone to the hospital asking for more pain medication.

Bonnar’s aggressive and erratic behavior unsettled staff however who repeatedly asked him to leave and escorted him outside, where police then arrested him.

Despite his troubles in later life, Bonnar is still a fighter who is fondly remembered by UFC fans for his wars in the Octagon and charismatic personality, while Dana White was among those who paid tribute to him after his death.

“Stephan Bonnar was one of the most important fighters to ever compete in the Octagon,” Dana White said in a UFC press release at the time. “His fight with Forrest Griffin changed the sport forever, and he will never be forgotten. The fans loved him, related to him and he always gave them his best. He will be missed.”

Ross launched MMA Insight (previously in 2009 as a way to channel his passion for the sport of mixed martial arts. He's since penned countless news stories and live fight reports along with dozens of feature articles as the lead writer for the site, reaching millions of fans in the process.