It's true that nitrous is a very short lasting trip. However, the intensity and euphoria more than make up for it. The body high is incredible. You may have to do it a few times to build a reverse-tolerance to feel the full effects. Nitrous gets a bad name simply because it is an inhalant (LIKE DUST OFF), but when used responsibly it is very safe. It falls under the same drug-category as DXM; Dissociative Anaesthetic.

http://www.erowid.org/chemicals/nitrous/nitrous.shtml