Final answer:
The most common side effect of nitrous oxide is dizziness or lightheadedness. Other common side effects include nausea, vomiting, and headaches.
Step-by-step explanation:
The most common side effect of nitrous oxide is dizziness or lightheadedness. When nitrous oxide is inhaled, it can cause a brief alteration in the balance of oxygen and carbon dioxide in the body, which can lead to feelings of dizziness. Other common side effects include nausea, vomiting, and headaches.
It is important to note that nitrous oxide is generally safe when used in controlled medical settings. However, prolonged or excessive exposure to nitrous oxide can have more serious side effects, such as nerve damage or vitamin B12 deficiency.