Nitrous oxide, also sometimes called laughing gas, is a colorless gas that is used in medicine and dentistry as an anesthetic. It is also used as a fuel additive and in rocketry. When inhaled, it causes a feeling of euphoria and relaxation. Nitrous oxide is found in small quantities in the Earth’s atmosphere, but it can be produced commercially by heating ammonium nitrate.
At room temperature and pressure, nitrous oxide is a non-flammable gas. It has a sweet, slightly metallic taste and smell. Nitrous oxide has been used medically since the early 1800s when it was first synthesized by Humphry Davy. Today, it remains one of the most popular anesthetics because it is relatively safe for both patients and medical personnel. Inhalation of nitrous oxide can result in dizziness, nausea, vomiting, loss of consciousness, and death if too much is inhaled (this is rare).
Nitrous oxide inhibits mitochondrial respiration leading to cellular hypoxia which then triggers apoptosis (cell death). This makes nitrous oxide useful as an anticancer agent. The mechanism of action for this effect was elucidated in 2010 by researchers at the University of California – San Francisco who found that NO inhibits complex I of the electron transport chain resulting in ATP depletion and cell death. In addition to its use as an anticancer agent, other potential therapeutic uses for nitrous oxide include treatment of Alzheimer’s disease, stroke, pain relief, myocardial infarction (heart attack),and anxiety disorders.