Guillain-Barré syndrome (GBS) damages the peripheral nervous system. That’s the nerves outside the brain and spinal cord. They help the central nervous system communicate with the rest of your body, including the skin, heart, and muscles. Chronic inflammatory demyelinating polyneuropathy (CIDP) is closely related to GBS with many of the same symptoms, but CIDP lasts much longer and if not caught earlier enough, can cause lasting effects.