Nitrous Oxide

Nitrous oxide, often referred to as “laughing gas,” is a colorless, non-flammable gas with a slightly sweet odor and taste. It is commonly used in dentistry for its anxiolytic and analgesic properties.

Nitrous oxide acts on the central nervous system, providing a calming effect and reducing anxiety. It also has mild analgesic properties, which help in managing pain during dental procedures.

Nitrous oxide is typically administered through a mask that covers the nose. It is mixed with oxygen in varying concentrations (usually 25-50% nitrous oxide) and inhaled by the patient. The gas takes effect quickly, within a few minutes, and the level of sedation can be adjusted easily by the dentist.


  • Anxiety Reduction: Helps patients feel more relaxed and less anxious, making it particularly useful for those with dental phobia.
  • Pain Management: Provides mild analgesic effects, reducing discomfort during procedures.
  • Quick Onset and Recovery: Effects are felt rapidly, and recovery is usually swift. Patients can often resume normal activities shortly after the procedure.
  • Adjustable Levels: The level of sedation can be easily controlled and adjusted throughout the procedure.
  • Safety: When used properly, nitrous oxide is considered very safe with minimal side effects.


Nitrous oxide is suitable for a wide range of dental procedures, including:

  • Routine cleanings for anxious patients
  • Minor dental procedures such as fillings, crowns, and extractions
  • More complex procedures like root canals or periodontal treatments


While nitrous oxide is safe for most patients, there are some contraindications:

  • Respiratory issues: Patients with severe chronic obstructive pulmonary disease (COPD) or other significant respiratory conditions may not be good candidates.
  • Pregnancy: It’s generally advised to avoid nitrous oxide during the first trimester of pregnancy.
  • Certain psychiatric conditions: Patients with severe psychiatric disorders might not respond predictably to nitrous oxide.
  • Vitamin B12 deficiency: Chronic exposure can lead to a decrease in vitamin B12 activity, affecting DNA synthesis and cell growth.

Side Effects

Most patients tolerate nitrous oxide well, but potential side effects can include:

  • Nausea and vomiting, particularly if the patient has eaten recently
  • Dizziness or light-headedness
  • Headache
  • Shivering