I don't think it was Nyquil...was it? Doxylamine is in Unisom sleep aid. And some people
get paradoxical excitation from antihistamines. Doxylamine is very sedating and has potential
to be very agitating.

What people do... and I used to field those calls is:
Take the OTC sleep aid.... wait a few minutes...nothing happens.

Rummage around in the house and find Valium (or another tranq) and take that.
Wait a few minutes, nothing happens...remember this was in the DAYTIME.

Rummage around some more...perhaps call ME up... by this point. ( I used to work midnights and
calls like this were very common).

Narcotics do cause agitation in some people..sometimes. Insomnia.
I haven't seen a report yet explaining the narcotic use for what kind of pain?

So he may have taking the narcotics, got agitated and then tried all the rest.
Benzos are respiratory depressants, and added up with the narcotics to depress his breathing reflex.

Once you are impaired with a strong drug, judgement become very poor and
one loses track of what one is doing. This is where sloppy doctors come in.
I suspect he had many meds from many doctors.. I can't see one doctor doing this...If so it is very unethical and dangerous to provide so much.