Which anesthetic is known to potentially cause allergic reactions after prolonged use?

Benzocaine is a topical anesthetic that is known for being associated with allergic reactions, particularly when used over an extended period. This anesthetic can cause sensitization in some patients, leading to allergic contact dermatitis. In cases where it is applied frequently or for a prolonged duration, the risk of an allergy increases, potentially resulting in a range of adverse reactions in sensitive individuals.

In contrast, lidocaine, articaine, and mepivacaine are local anesthetics commonly used in dental procedures, and they are generally less associated with allergic reactions compared to benzocaine. While these anesthetics can cause adverse effects in some patients, they have a lower incidence of significant allergic reactions, especially with prolonged use, than benzocaine. Thus, while allergic reactions can happen with any anesthetic, benzocaine is particularly noted for this risk, especially when used repeatedly.