Many people carry Narcan (the most common form of naloxone, is used to counteract opioid overdosing). It is a nasal spray. It is standard equipment for paramedics. Since I'm a patient at a pain clinic, I have to have some in my house and my family (also roommates, if I had any) know where it is and how to use it.
Critically, Narcan is pretty safe to use on most people who aren't suffering an opioid overdose, so it's likely to be administered before bloodwork gets back.
