Which amide anesthetic is metabolized in the plasma, much like esters?

Which amide anesthetic is metabolized in the plasma, much like esters?

• A. Bupivicaine
• B. Prilocaine
• C. Articaine
• D. Mepivicaine

Answer: (C)

Articaine stands out because it contains an ester linkage in addition to its amide bond. That ester group allows plasma esterases to hydrolyze part of the molecule directly in the circulation, so it is metabolized in plasma much like ester anesthetics. The other common amide locals are mainly broken down in the liver by hepatic enzymes, so they don’t undergo significant plasma metabolism. This is why articaine behaves with an ester-like, faster plasma clearance compared with bupivacaine, prilocaine, or mepivacaine.

Articaine stands out because it contains an ester linkage in addition to its amide bond. That ester group allows plasma esterases to hydrolyze part of the molecule directly in the circulation, so it is metabolized in plasma much like ester anesthetics. The other common amide locals are mainly broken down in the liver by hepatic enzymes, so they don’t undergo significant plasma metabolism. This is why articaine behaves with an ester-like, faster plasma clearance compared with bupivacaine, prilocaine, or mepivacaine.