Final answer:
Lignocaine is a local anesthetic that blocks voltage-gated sodium channels to prevent the transmission of pain signals. This causes numbness and pain relief. However, it can also have side effects like tingling lips and cardiovascular collapse.
Step-by-step explanation:
Lignocaine is a local anesthetic that works by blocking voltage-gated sodium channels. When these sodium channels are blocked, the transmission of pain signals from nerves to the brain is prevented. This is why blocking voltage-gated sodium channels with lidocaine causes numbness and pain relief. However, it's worth noting that while lidocaine can provide effective local anesthesia, it can also have side effects such as tingling lips and, in rare cases, cardiovascular collapse.