Final answer:
Benzocaine is the drug that is not an amide local anaesthetic; it is an ester. The other drugs listed - Bupivacaine, Lignocaine, and Prilocaine - are amide local anaesthetics.
Step-by-step explanation:
The question is asking which of the following drugs is not an amide local anaesthetics: Bupivicaine, Lignocaine, Prilocaine, or Benzocaine. Among the options, Benzocaine is the only one that is not an amide-type local anaesthetic; it is an ester-type. Local anaesthetics like Bupivacaine, Lignocaine (also known as Lidocaine), and Prilocaine are classified as amides and work by temporarily blocking sodium channels, preventing nerve conduction which leads to a reversible loss of sensation in a localized area.
Local anesthetics are used in various medical settings to induce a temporary numbing effect to perform surgical or diagnostic procedures without pain. Both amide and ester local anaesthetics have similar uses but differ in their chemical structure and, sometimes, in their metabolism and allergic potential.