The shelf life of local anesthetics without epinephrine is how many months?

The shelf life of local anesthetics without epinephrine is how many months?

• A. 12 months
• B. 18 months
• C. 36 months
• D. 60 months

Answer: (C)

Stability of the drug in the solution drives shelf life. Local anesthetic bases (like lidocaine) are chemically stable, and when epinephrine isn’t included, there’s no added antioxidant protection needed for a vasoconstrictor. Epinephrine solutions require antioxidants (such as sodium metabisulfite) to prevent oxidation, which introduces aging limits and reduces overall shelf life. Because the base anesthetic can remain potent longer without those oxidizing risks, unopened non-epinephrine cartridges are commonly listed as stable for about 36 months if stored properly. That’s why the best choice is 36 months.

Stability of the drug in the solution drives shelf life. Local anesthetic bases (like lidocaine) are chemically stable, and when epinephrine isn’t included, there’s no added antioxidant protection needed for a vasoconstrictor. Epinephrine solutions require antioxidants (such as sodium metabisulfite) to prevent oxidation, which introduces aging limits and reduces overall shelf life. Because the base anesthetic can remain potent longer without those oxidizing risks, unopened non-epinephrine cartridges are commonly listed as stable for about 36 months if stored properly. That’s why the best choice is 36 months.