Nitrous oxide (N₂O) is a gas at room temperature and pressure. It is used primarily for anesthesia but is also used as a propellant for whipped cream or to boost octane levels in racing cars. N₂O was extensively studied by Sir Humphrey Davy, who presented a detailed description of his subjective experiences under the influence of N₂O, as well as self-reports by friends and colleagues of their own experiences while inhaling the gas. Sir Davy's treatise was a thorough, systematic, and extensive characterization of N₂O and was a foreshadowing of two centuries of research to follow. Sir Davy's...

Nitrous oxide (N₂O) is a gas at room temperature and pressure. It is used primarily for anesthesia but is also used as a propellant for whipped cream or to boost octane levels in racing cars. N₂O was extensively studied by Sir Humphrey Davy, who presented a detailed description of his subjective experiences under the influence of N₂O, as well as self-reports by friends and colleagues of their own experiences while inhaling the gas. Sir Davy's treatise was a thorough, systematic, and extensive characterization of N₂O and was a foreshadowing of two centuries of research to follow. Sir Davy's and subsequent research consisted of the dose-response assessment of subjective effects of acute and repeated N₂O administration, examination of individual differences, and the study of environmental and organismic determinants/modulators of N₂O effects. This chapter presents the results of such experiments in a chronological framework and attempts to detail the various characterizations of N₂O across the years since its discovery.