The most potent and longest acting anaesthetic agent is:: (A) Dibucaine, (B) Tetracaine, (C) Bupivacaine, (D) Lignocaine
Answer is A. Dubucaine is the most potent, most toxic , and longest acting local anesthetic Cinchocaine or dibucaine is an amide local anesthetic. Among the most potent and toxic of the long-acting local anesthetics, current use of cinchocaine is generally restricted to spinal and topical anesthesia. From KD Tripati 7th edition Page no 367