"Laughing gas" (Nitrous oxide) was first used as an anesthetic and was widely used in dental and surgical operations from 1844. Later, it was gradually replaced by a better anesthetic. Nitrous oxide is also a recreational drug that has been abused due to its euphoric effects and ability to cause laughter when inhaled. But the vast majority of people who take it don't know how dangerous it is. When inhaling laughing gas, may cause sudden asphyxia due to too little oxygen.

It can also cause nerve damage, resulting in reduced intelligence, audiovisual ability, and hand flexibility in a short time. Long-term consumption may lead to symptoms such as vitamin B deficiency, muscle paralysis, and even paralysis.