Nitrous oxide (N2 O), commonly known as laughing gas or happy gas, was first discovered in 1793 by the English scientist Joseph Priestly and has been used for more than 150 years. It has remained one of the most widely used anesthetics in both dental and medical applications.

Nitrous oxide is small inorganic chemical molecule and may also be known as dinitrogen oxide or dinitrogen monoxide. It is a colorless and nonflammable gas with a slightly sweet odor.

Nitrous oxide is the most commonly used inhalation anesthetic in dentistry and is commonly used in emergency centers and ambulatory surgery centers as well. When used alone, it is incapable of producing general anesthesia reliably, but it may be combined with other inhalation and/or intravenous agents in deep sedative/general anesthestic techniques. However, as a single agent, it has impressive safety and is excellent for providing minimal and moderate sedation for apprehensive dental patients. 

Nitrous oxide acts as an N-methyl-D-aspartate (NMDA) receptor antagonist. This is different from other volatile anaesthetic agents that modulate (usually potentiate) the activity of gamma-amino butyric acid-A (GABAA) receptors and inhibit neuronal potassium channels (TREK-1) among other suggested targets. The NMDA receptor is a glutamate binding, non-selective ion channel involved in synaptic plasticity and memory formation. The GABAA receptor is the main inhibitory, chloride-ion selective, ligand-gated channel of the central nervous system (CNS). Through different mechanisms, nitrous oxide and GABAA modulators act synergistically to induce amnesia and hypnosis. Thus nitrous oxide is often referred to as a ‘volatile-sparing agent’.

Unlike other anesthetics, nitrous oxide produces a mild analgesic effect at subanesthetic concentrations. The mechanism for this effect most likely involves an interaction with the endogenous opioid system because it is abolished by administration of the opioid antagonist, naloxone.

Nitrous oxide is not supposed to put you to sleep, although some may fall asleep. The point is to relax you, and for you to still feel conscious so you can give us feedback on your level of anxiety. The gas is inhaled through a mask you wear over your nose. The Nitrous oxide will make you calm.

Nitrous oxide is a safe, common sedation method that's appropriate for adults and children. Yet, side effects can occur after use. Most side effects are mild and reversible and don't cause lasting damage.

Nitrous oxide is stored in high pressure gas cylinders as a liquid under pressure. Rapid opening of the valve can cause the discharged gas to re-liquefy. This liquid can cause cold burns if in contact with the skin. Cylinders should only be used in the vertical position with the valve uppermost.

You can check our Central Gas Stations for safe use of N2O in hospitals.

Sources: 

https://academic.oup.com/bjaed/article/16/3/87/2897753

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2614651/