Why is sodium bisulfite added to dental cartridges?

Sodium bisulfite is added to dental cartridges primarily to prevent the oxidation of epinephrine. Epinephrine is commonly used in local anesthetics to prolong the duration of anesthesia and to reduce bleeding in the surgical area by causing vasoconstriction. However, epinephrine is sensitive to oxidation, which can lead to a decrease in its effectiveness.

By incorporating sodium bisulfite into the formulation, the oxidation process is inhibited, allowing the epinephrine to remain stable and effective throughout the shelf life of the product. This is crucial for maintaining the potency of the anesthetic solution, ensuring that dental practitioners can rely on its performance during procedures.