This fact is from LA Pharmacology in Pharmacology. It is a commonly tested concept in NEET MDS examinations. Understanding this fact is crucial for answering MCQs correctly.
Esters = metabolized by plasma pseudocholinesterase = procaine
Amides = metabolized in liver = lidocaine
Onset determined by pKa = lower pKa faster onset
Duration determined by protein binding = higher binding longer duration
Articaine = unique hybrid amide with ester group
Prilocaine = least toxic amide
Bupivacaine = most cardiotoxic.