He took too much percocet. Probably had an anti depressant in him also. That’s where the accidents happen. You can die from a Xanax and a Vicodin. Been there and didn’t mean to do it.
Yes, during my career my crews and I responded to a lot of people who had lost consciousness after taking the wrong combination of drugs or drugs and alcohol. Most of them lived to tell the tale. The majority who died had taken illicit drugs where the potency often varies. Some died because they intentionally took a lethal overdose then called someone to save them after it was too late.