Police and paramedics found Sean Bull dead at his home, on Chawn Hill, in Lye, Stourbridge, on December 9.
The alarm was raised by Mr Bull's carer who was unable to enter the property and alerted police, Black Country Coroner's Court was told.
Officers forced entry into the address where his body was found. Paramedics confirmed he was dead at the scene.
A digital autopsy revealed Mr Bull had high levels of heroin and morphine in his blood alongside cocaine.
Doctors concluded his cause of death was a heroin and morphine overdose, the court heard. A contributing factor was also schematic heart disease.
Area coroner for the West Midlands, Joanne Lees, said Mr Bull had a history of mental health issues but concluded his death was not suicide.
She recorded his death as drug-related.
Mrs Lees told the court: "There is clear evidence of cocaine and high levels of heroin and morphine in the blood of the deceased.
"I am satisfied this was his cause of death. There is no evidence of this being suicide or being an accident. I record his death as drug-related."