[stryk]

I see. I didn't know that, that's interesting. Question you may be able to answer: The naloxone/Narcan sticks that EMTs and some police have, they also pass them out at needle exchanges, etc. is that why are those applied in the nasal passage?

I'm a layman, but if i'm guessing right the term for this might be 'bioavailability' of the drug, is that correct? for example drug A may be absorbed faster and more easily through the digestive system over snorting. And then of course IV is the quickest way for just about anything, yea?

[L_Rahman]

You used the correct term - bioavailability describes the fraction of a drug dosage that can enters the bloodstream.

Your example however makes an incorrect assumption. Bioavailability from snorting a powdered drug is higher than oral ingestion. When snorted, the drug passes through the thin lining of the nose and enters the bloodstream directly. When ingested orally, the drug has to make it through the chaos of the stomach and small intestine, get through the hepatic pathway (stomach and intestinal lining to liver to general bloodstream) before it reaches the rest of the body.