Polyneuropathy refers to damage occurring simultaneously in multiple nerves that form the peripheral nervous system. This condition is a disease that leads to the loss of nerve function, causing various neurological symptoms. The nervous system consists of two main parts: the central nervous system and the peripheral nervous system. The peripheral nervous system includes nerve roots emerging from the spinal cord, nerve plexuses, and peripheral nerves that carry stimuli to the body's limbs and organs. Nerve damage due to polyneuropathy typically begins in the farthest points from the brain, namely the toes and fingertips. It typically manifests as a loss of sensation and reduced movement in the muscles of the hands and feet, and these symptoms can progress upwards. "Poly" means many, "neuro" refers to nerves, and "pathy" signifies damage. The prevalence of polyneuropathy increases with age.