Nitrous oxide can be used to relieve anxiety and lessen pain for almost any type of dental treatment. Its use often depends more on a patient’s preferences than medical need.

The use of nitrous oxide may be recommended for patients with the following conditions:

• Mild to moderate dental anxiety. Nitrous oxide may lessen a patient’s fear and make dental treatment more tolerable. This can ensure patients receive adequate dental care despite their fear.
  
  
• Hypersensitive gag reflex. Nitrous oxide does not completely eliminate a patient’s gag reflex, but does lessen its sensitivity. This may make dental treatment more comfortable for patients with hypersensitive gag reflexes.
  
  
• Cardiac conditions. Because nitrous oxide is a mild sedative that does not alter a patient’s blood pressure or heart rate, it is a safe form of anxiety and pain relief for patients with cardiac conditions.

Nitrous oxide may also be recommended for patients who do not receive local anesthesia (e.g., due to allergies or refusal of local anesthesia).