ב''ה,
Technically if you're going to fiddle with opiates without having distaste for life, Narcan is everywhere, there are numerous opportunities to get it free and without questions, and it's probably less unpleasant to be doing that to yourselves than with the medical questions and medical billing, although probably quite dysphoric in the immediate moment.
That said opiate respiratory depression is a thing and waking up with brain damage isn't fun if waking up, so I have no idea what rule of thumb to use here and not in the mood to look up how much codeine that even is, but if someone isn't breathing or lips are turning blue that may be a decision point. Also rolling drunk people on their sides so they don't choke on any vomit is common courtesy.