snorting burns nose less over time?

[blackdb1]

Swim was just looking over the adderall section and seen someone posted that adderall burns the nostrils. Well this got swim thinking... When swim was first experimenting with sniffing different substances it used to burn like hell!!! But after snorting all kinds of different substances swim noticed the burning to be significantly less over time!? This makes him wonder did he just get used to the burning or are the substances deteriorating nerves or something over time? Swim has been with other people in the past month and heard them say after snorting that oxycodone, adderall, etc. burned the shit out of their nose while swim felt no burning at all.
Like swim said that thread just got him wondering and he's sitting home bored so decided to make a thread about it.