Nitrous is even used in diving to prepare divers for nitrous-like effects. The following is taken from the CA penal code. Any person who possesses nitrous oxide or any substance containing nitrous oxide, with the intent to breathe, inhale, or ingest for the purpose of causing a condition of intoxication, elation, euphoria, dizziness, stupefaction, or dulling of the senses or for the purpose of, in any manner, changing, distorting, or disturbing the audio, visual, or mental processes, or who knowingly and with the intent to do so is under the influence of nitrous oxide or any material containing nitrous oxide is guilty of a misdemeanor. This section shall not apply to any person who is under the influence of nitrous oxide or any material containing nitrous oxide pursuant to an administration for the purpose of medical, surgical, or dental care by a person duly licensed to administer such an agent. Some residual effects may last up to several minutes later.
Nitrous gas permeates the lipid membranes and produces an anaesthetic effect.
Long term or heavy use can have unpleasant effects. Here are some quotes regarding the dangers of nitrous use. While light use is not hazardous, here are some common sense errors to avoid. After several deep breaths of air, I inhale nearly a lungful of nitrous and pull some air down on top and then hold my breath. Within seconds, a light tingling can be felt which seems to increase in frequency.