Houston's Cause of Death was Accidental Drowning?

Really? Do you mean that she fell asleep in a bath tub full of water? C'mon man, we need a little more thought than that.

It seems to me she must have lost consciousness while in the tub, which suggests to me either some primary central nervous system depression, or the same effect secondary to a loss of cardiac function. Although a fair number of drugs were found in her room and in her body, they were not found in concentrations high enough to be a sufficient cause by themselves.

It looks like the circumstances surrounding the death, i.e being found dead under water; and the drug use history, especially cocaine use; together with an absence of any convincing morphologic cause on autopsy, led  to the coroner's conclusion.

But what caused the loss of consciousness in a potentially dangerous environment? Could she have suffered some CNS or cardiac malfunction because her drug levels were low enough to be dangerous? Could her tolerance for the drugs have sunk so low that even small amounts might be dangerous? What is the mechanism of death in cocaine and poly-pharmacy deaths? If the drugs increased the probability of a sudden CNS or cardiac event, even when still present in small amounts, shouldn't they be listed as the probable cause of death, in that they initiated the process that led to death?

Curious people want to know.