Guillain–Barré syndrome (GBS) (, ), sometimes Landry's paralysis or Guillain–Barré-Strohl syndrome, is an acute polyneuropathy, a disorder affecting the peripheral nervous system. Ascending paralysis, weakness beginning in the feet and hands and migrating towards the trunk, is the most typical symptom, and some subtypes cause change in sensation or pain as well as dysfunction of the autonomic nervous system. It can cause life-threatening complications, in particular if the breathing muscles are affected or if there is autonomic nervous system involvement. The disease is usually triggered by an infection.