More details are surfacing about Michael Chiarello's final days. 

The former Food Network star died in October at age 61 after being treated for an acute allergic reaction at a hospital in Napa, Calif., his company Gruppo Chiarello said in a statement Oct. 7. 

"The doctors don't know what caused the allergic reaction and neither does the family," a rep for Gruppo Chiarello told People at the time. "They may never know."

An anaphylactic shock he suffered as a result of the allergic reaction ultimately led to a fatal heart attack, the Napa County Coroner's Office told multiple outlets. Cocaine was found his system at the time of death, per the coroner, though authorities do not believe he overdosed.

Officials have now revealed more information about his health prior to the episode. Michael's estranged wife Eileen told authorities the chef said "he was on a new weight loss drug called Ozempic or something similar" prior to his passing, per a report from the Napa County Sheriff-Coroner obtained by Entertainment Tonight.

"It was her understanding the drug was a diabetic medication that had recently found use as a weight loss medication," the report said. "She knew Ozempic was given by injection, but did not know how it was administered to [Michael]." 

Michael's partner Kellie told authorities that he had instead been taking injections of tirzepatide—a medicine used to treat adults with type 2 diabetes—once per week for the last three months, according to the document.

While Kellie was not sure the last time he took the medication, the coroner's report said "as far as she knew, he hadn't taken the medication in the last two weeks."

Tirzepatide has also been taken for weight loss, per CNBC, but the coroner's report does not state whether Kellie shared what he was using it for.

On Oct. 5, the day Michael was hospitalized, the Next Iron Chef star experienced hives all over his body and facial swelling, according to Kellie. After giving him Benadryl, she started driving him to the hospital but he stopped breathing during the journey. Kellie then called 911 and he was rushed to the hospital, where he died the following day.

In the wake of his death, a rep for Ozempic's drugmaker Novo Nordisk issued a warning that the type 2 diabetes drug, which several celebs have used for its weight loss-inducing properties, should be taken under the supervision of a healthcare provider.

"At Novo Nordisk, patient safety is a top priority," a spokesperson said in a statement to E! News. "We work closely with the U.S. Food and Drug Administration to continuously monitor the safety profile of our medicines. Additionally, our medicines should only be prescribed after a close consultation between a healthcare provider and a patient." 

The statement added in part, "Novo Nordisk is committed to the responsible use of our medicines."

For the latest breaking news updates, click here to download the E! News App