Nitrous Oxide, N2O, also called laughing gas, is a colorless gas with a pleasant sweetish odor and taste which when inhaled produces insensibility to pain proceeded by mild hysteria or laughter.
The physiological effects of using nitrous oxide last approximately a minute for a lungful of nitrous and then mainly dissipate. Some residual effects may last up to several minutes later. Nitrous gas works by infusing the membranes of the body and produces and anesthetic effect.
Nitrous oxide is used in roughly one third of dental practices in the United States. The benefits of nitrous oxide are many and the risks are few. The gas is administered with a comfortable mask placed over the nose and the patient is instructed to breathe in through the nose and out through their mouth. As a precaution, patients should not eat anything for about two hours prior to use. The patient begins to feel a level of sedation in anywhere from 30 seconds to 3 or 4 minutes. The cheeks and gums will also begin to feel numb in about a third of the patients.
After the treatment is completed, the patient is given pure oxygen to breath for about five minutes, and all the effects are usually reversed. Unlike IV Sedation or Oral Sedation, the patient can almost always leave the office by themselves without an escort.