Although heroin is not the drug of choice it is known that an average bag of heroin would be a .3 or 300 mgs. A person of zero tolerance would likely be good with 100 to 200 mgs for the first time.
So two to three days?
However be warned that 600 mgs of heroin was sniffed once which gave 20 minutes of warmth and mild euphoria and then abruptly ended afterwards. Quite disappointing. However a moderate to high oxycodone tolerance was had at the time.
The point is there is a reason the predominant method of administration is intravenously.
Bioavailability is lower when taken intranasally.
However intravenous administration should definitely be avoided.
The best piece of advice would be to start with 100 mg, wait 15 minutes, and decide if a higher or lower dose is needed and plan from there.
Good luck and be safe
