How does snorting (insufflating) opiates get a person high?
In the nose, there is a mucosal lining which can absorb certain chemicals depending on how fat-soluble the molecule is. The more fat-soluble the opiate is, the better absorbed it will be. One opiate that is extremely fat-soluble is fentanyl, and not too far behind is its opiate cousin diacetylmorphine, also known as heroin. It is important to remember that insufflation is not without consequence. In general, snorting anything could potentially wear away the tissues in the nose until there is a gaping hole or the person can whistle through his/her nostril.
