Nitrous oxide is a chemical mixture of nitrogen and oxygen that’s used as a dental anesthesia for painful or stressful procedures. It’s more commonly known as laughing gas for the giddy and/or calm effects it has on patients. It is odorless, colorless, doesn’t cause irritation as some gases do, and has very few and limited side effects when administered correctly.


Discovery and History

An English chemist Joseph priestly discovered nitrous oxide in 1772 when running nitrogen through water to removed toxins. He’d hoped to use it as a preserving agent, but it yielded no such effects. In 1798, another English Chemist Humphry Davy began experimenting with its physiological effects in the hopes of using it for patients at his workplace, Thomas Beddoes’s Pneumatic Institution. He officially named it, and also dubbed it “laughing gas” after using it himself for a toothache and in social situations as entertainment.



Despite its possible medical adeptness, nitrous oxide remained out of clinics and hospitals for many years. In that time, it became a form of entertainment in circuses and traveling shows, where patrons would pay to enjoy its euphoric effects. Throughout the 1800s, it was a form of amusement for collectives of young people.

The first dentist to use nitrous oxide to numb pain in a dental extraction was Horace Wells in December 1844. He used it successfully but couldn’t convince other dentists to follow his lead. From 1863 to 1866, Wells’ assistant Gardner Quincy Colton successfully began to use it in all his New Haven and New York dental clinics, and his success convinced other dentists to follow suit. Though dentists had much success with the gas, hospitals found it wasn’t strong enough solo for major surgeries.


Dental Use, Sensations, Possible Side Effects

When used in a dental setting, nitrous oxide is perfect for depressing pain and calming nervous or anxious patients through a difficult or time consuming procedure. The gases are mixed and administered through a mask placed on the patients face and remains there until the procedure is complete. It is safe for all ages, and the patient remains alert, being able to speak or respond to dentist’s questions or directions. N2O concentration should always be gradually increased with each use, as tolerance can vary with each visit for a particular patient.


Correctly administered nitrous oxide can make you feel light headed or warm, cause tingling or vibrating sensations in your limbs, or make your body feel heavy or like it’s floating. The intention of a dentist is to have patients feel peaceful and comfortable. Some people do experience side effects if the nitrous oxide concentration is too high, including sleepiness, nausea, or flashbacks. If you experience these, don’t be afraid to remove the gas or let your dentist know right away.


Other Uses& Information

Aside from dentist use, nitrous oxide has many other applications. It is a non-toxic oxidizer for rocket motors, allowing safe flight and easy conversion into breathable air. It’s also the “juice” used in small combustion engines for racing, offering more oxygen to burn the fuel more quickly and provide more power. Additionally, it’s used as a food additive for specialties that come in aerosol spray cans such as cheese whiz, whipped cream, and cooking sprays. Nitrous oxide is also used in snack bags to combat bacterial growth and displace oxygen.


There are some questions about the neurotoxicity of nitrous oxide, but case studies show that limited and temporary exposure doesn’t harm the human nervous system. It is one of many greenhouse gases with a high global warming potential, and is a natural bi-product of nitrification and denitrification in soil. Another concern is for people with subclinical vitamin B-12 deficiencies, as Nitrous Oxide oxidizes the vitamin at high rates.