Nitrous oxide, commonly known as laughing gas or nitrous, is a chemical compound with the formula N2O. It is an oxide of nitrogen and is used in medical and dental procedures as an anesthetic and analgesic. It is also used in motor racing as a performance-enhancing drug. Nitrous oxide has a sweet smell and taste, and when inhaled it produces feelings of euphoria. In high concentrations it can cause dizziness, nausea, and even loss of consciousness. Long-term use can lead to vitamin B12 deficiency and nerve damage.