Local Anesthetic Metabolism

Cocaine is an ester but undergoes significant metabolism in the liver. 2. Metabolism of Amide Local Anesthetics

Amide local anesthetics (e.g., lidocaine, bupivacaine, ropivacaine, mepivacaine) contain an amide linkage and are generally more stable in solution than esters. Basic pharmacology of local anaesthetics - PMC - NIH local anesthetic metabolism

The Phase I metabolites (often still active, but less potent and more toxic in some cases) undergo glucuronidation or further conjugation for renal excretion. Cocaine is an ester but undergoes significant metabolism