nitrous oxide + oxygen

Nitrous oxide + oxygen is a fixed combination inhaled medical gas used primarily for analgesia and sedation during minor surgical, dental, or obstetric procedures. The typical formulation is a 50:50 mixture of nitrous oxide (N2O) and oxygen (O2), which provides rapid-onset pain relief with anxiolytic and sedative effects while maintaining patient consciousness. Nitrous oxide acts as an NMDA receptor antagonist in the central nervous system, producing analgesic and dissociative effects. Oxygen supplementation prevents hypoxia associated with pure nitrous oxide use. The combination is widely used due to its fast onset (within minutes), short duration of action, minimal residual effects after discontinuation, and favorable safety profile when administered by trained professionals[1][5][8]. It is commonly indicated for procedural pain management in dentistry, labor analgesia, emergency care, minor surgery, and has investigational uses in treatment-resistant depression[5][6].

Brand names

EntonoxNitronox

Other names

laughing gas and oxygenN2O/O2 mixturenitrous oxide/oxygen mixture