Final answer:
Giving medication to block pain at the spinal cord level is done as an epidural injection. Lidocaine is a local anesthetic that works by blocking voltage-gated sodium channels, preventing nerve signal conduction and subsequently causing numbness and pain relief.
Step-by-step explanation:
Giving medication to block the sensation of pain at the level of the spinal cord is done as a epidural injection. Local anesthetics like lidocaine work by blocking nerve conduction when applied to nerve tissue. These anesthetics prevent the initiation and transmission of sensory impulses by acting on the nervous system, which can include both sensory and motor paralysis in the area innervated.
Lidocaine is a local anesthetic that achieves its effect by inhibiting voltage-gated sodium channels. Blocking these channels prevents the conduction of nerve signals, which is necessary for the perception of pain. The interruption of the signal transmission results in numbness and relief from pain.
Psychoactive drugs play various roles in medicine, including general anesthesia, which induces unconsciousness and pain blockage using drugs like halothane and ketamine. On the other hand, for pain management without affecting consciousness, analgesic drugs like opioids—morphine and codeine—are used, which can become narcotics at higher doses by causing drowsiness and loss of consciousness.