Nitrous oxide is a longstanding, proven form of light sedation. It's been used in dental offices around the world for decades. Called inhalation sedation, also known as "laughing gas," nitrous oxide is breathed during your dental procedure with a mixture of oxygen. Before your procedure begins, the dentist or assistant will place a small nasal hood over your nose. The machine is activated and adjusted to the right combination of N2O to O2. You simply breathe normally, and soon feel the effects of the mild sedative.
As you continue to breathe in nitrous oxide, the GABAA receptors in your brain inhibit the uptake of certain neurotransmitters; those that instigate anxiety. Additionally, it stimulates the release of norepinephrine, which has an analgesic effect throughout the body. In these two actions, nitrous oxide both reduces anxiety and increases your pain threshold. During your treatment, you'll be awake and alert but will feel less discomfort and may have a euphoric or "giddy" sensation.