Final answer:
Lidocaine blocks voltage-gated sodium channels to relieve pain, while epinephrine treats hypersensitivity reactions.
Step-by-step explanation:
Lidocaine is a local anesthetic that works by blocking voltage-gated sodium channels. When these channels are blocked, they are unable to transmit electrical signals, which are responsible for the sensation of pain. Without the transmission of pain signals, the area where the lidocaine is applied becomes numb, resulting in pain relief.
Epinephrine, on the other hand, is used in the treatment of hypersensitivity reactions, such as severe allergic reactions. It acts by constricting blood vessels and relaxing airway muscles. By doing so, epinephrine helps to alleviate the symptoms of an allergic reaction and prevent life-threatening complications.