Mourners have been sharing their sorrow over the death related to an apparent opioid overdose of Dennis Shields, 51, who was found on Friday after passing away in his New York City home.
Those publicly grieving the loss of Shields include the likes of film and television executive Brian Koppelman, famed personality Mehmet 'Dr. Oz' Oz, and his estranged wife, Jill, with whom he shared four children.
His on-again-off-again romantic partner Bethenny Frankel, whom he had known for more than two decades, has not commented personally, but sources say she is 'heartbroken.'
Additional outpourings of sadness, sympathy and support came from Shields' many business colleagues, as well as Frankel's castmasts from the BravoTV's Real Housewives franchise.
Shields died unexpectedly after it's believed he suffered a heart attack while overdosing on oxycodone, an addictive opioid he was taking to treat back pain.
He was at home in Trump Tower at the time of his death, with his housekeeper, who he asked to administer Narcan, an opioid blocker, according to TMZ.
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Mourners have been sharing their sorrow over the death related to an apparent opioid overdose of Dennis Shields, 51 (left), who was found on Friday after passing away in his New York City home; Shields had been a long-time friend of Bethenny Frankel (right), and a more recent romantic partner, with the two of them pictured here in New York City in June of 2016
Shortly before 9am on Friday, Shields asked his housekeeper to go to a pharmacy to buy him Narcan, after taking multiple pills the night before.
At some point, according to TMZ, the housekeeper returned with Narcan, noticed he was unresponsive, called 911, and administered the Narcan, though it's not clear in what order these events unfolded, but Shields remained unresponsive.
Narcan works by knocking out opioids from the opiate receptors in a person's brain.
Sources tell DailyMail.com Shield's heart could not cope with the dosage of oxycodone he's believed to have taken, beginning on Thursday night.
Before his untimely death, Dr. Oz was just one of the many lives Shields touched.
'Sad to learn that Bethenny Frankel’s friend, Dennis Shields, lost his life to an apparent opioid overdose today,' Dr. Oz shared on Twitter on Friday.
'My thoughts are w/ Bethenny & all of Dennis’ loved ones. His death is another reminder that the opioid crisis has reached epidemic proportions & can touch everyone.'
Before his untimely death, Dr. Mehmet 'Dr. Oz' Oz was one of the many lives Shields touched
Koppelman, The co-creator of Showtime's 'Billions,' also shared his sadness over the passing of his long-time friend
Koppelman, The co-creator of Showtime's 'Billions,' also shared his sadness over the passing of his long-time friend.
'Dennis Shields, who died this morning, was my close friend for 30 years. One of the smartest, most generous, people I ever came across,' Koppelman tweeted on Friday.
'He was also one of the great storytellers in the world. And understood life’s endless absurdity in his bones. I loved him. And love his family.'
Frankel, who hasn't personally commented on Shield's death publicly, is reportedly 'heartbroken' over the death of her on-again-of-again boyfriend Dennis Shields.
Sources close to the Real Housewife of New York City told E! News: 'This is really bad. It's dreadful. She's known him for over 20 years. She's heartbroken.'
Frankel is reportedly 'heartbroken' at the loss of her on-again-of-again boyfriend who was found dead on Friday morning
Shields (pictured with Bethenny Frankel in 2016) was found dead on Friday morning
The medical examiner's car remained outside Trump Tower on Friday afternoon hours after the 51-year-old died reportedly after trying taking Narcan to reverse the effects of opioids
The medical examiner's truck is pictured leaving the building on Friday afternoon
At some stage before 9am, Shields lost consciousness and the maid called 911. He was pronounced dead by EMTs shortly afterwards.
Sources close to the businessman told DailyMail.com that his back had been 'acting up' recently and still hadn't recovered from a 2015 surgery.
They believe that he died of cardiac arrest because his heart 'could not cope' with the dosage of the powerful painkiller.
Frankel was unaware of the news on Friday morning and was adding to her Instagram story frequently until around noon (she is seen above in a selfie with her dog on Friday morning)
Frankel was at her home in Bridgehampton when he died. She appeared to be unaware of the tragedy and was uploading photographs and videos to her Instagram story until around noon.
She and Shields dated intermittently from 2016 onwards but always remained friends.
He appeared occasionally on the Bravo show in which she stars. The SkinnyGirl mogul has not commented on Shields' death.
Shields' estranged wife Jill, who he had four children with, told DailyMail.com she was 'devastated' by his death.