Nitrous Oxide

A gas that can cause general anesthesia. Nitrous oxide is sometimes given in the company of other anesthetic agents but it is not used today as the only anesthetic agent because the concentration of nitrous oxide needed to produce anesthesia is close to the concentration that seriously lowers the blood oxygen level and creates a hazardous hypoxic state.

Nitrous oxide figured in the history of anesthesiology. In 1840 a dentist named Horace Wells had the idea that, with the recently discovered "exhilarating or laughing gas", teeth might be extracted without pain. Under its influence he had one of his own teeth pulled in 1844 and afterwards frequently used it in his practice.

The pharmacological mechanism of action of N2O in medicine is not fully known. However, it has been shown to directly modulate a broad range of ligand-gated ion channels, and this likely plays a major role in many of its effects. It moderately blocks NMDA and β2-subunit-containing nACh channels, weakly inhibits AMPA, kainate, GABAC, and 5-HT3 receptors, and slightly potentiates GABAA and glycine receptors. It also has been shown to activate two-pore-domain K+ channels. While N2O affects quite a few ion channels, its anaesthetic, hallucinogenic, and euphoriant effects are likely caused predominantly, or fully, via inhibition of NMDA receptor-mediated currents. In addition to its effects on ion channels, N2O may act to imitate nitric oxide in the central nervous system, and this may be related to its analgesic and anxiolytic properties.

Adult: This gas must be used with close clinical supervision with hematological monitoring as required.

Child: Safety & Efficacy has not been established.

There are no known drug interactions and none well documented.

Pneumothorax, abdominal distension, suspected intestinal obstruction, bullous emphysema. It should also be avoided where the patient is unable to effectively make use of the gas delivery equipment such as maxillo-facial injuries, impaired consciousness, sedation or intoxication.

Generally well tolerated.

Pregnancy Category: Not Classified. FDA has not yet classified the drug into a specified pregnancy category.

Prolonged inhalation can also result in dryness of the mouth and discomfort.

General (Inhalation) anesthetics