A 70-year-old patient with a known allergy to amide local anaesthetics requires a minor skin excision. Which of the following agents is an ester local anaesthetic that should be considered as an alternative, assuming true allergy is to the amide class?
- A Procaine ✓
- B Bupivacaine
- C Ropivacaine
- D Lidocaine
Correct answer: A. Procaine
Explanation
Procaine is an ester local anaesthetic, while lidocaine, bupivacaine, and ropivacaine are amides. Cross-reactivity between amides and esters does not occur chemically, as they have different metabolic pathways (hepatic vs. pseudocholinesterase). Therefore, an ester is a safe alternative for a patient with an amide allergy.
Reference: Katzung's Basic & Clinical Pharmacology, 15th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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