Classically the Guillain Barre (or Landry Guillain Barre Strohl) syndrome is characterized by three features: (1) motor paralysis, (2) areflexia, and (3) respiratory failure. Typically the onset follows an upper respiratory infection or 'cold' (about 50% of the cases, suggesting an immune reaction and raising the question of a similar mechanism following swine flu innoculations) or some other incident (e.g., surgical procedures in about 10% of the cases) about 2 to 3 weeks prior to the onset of symptoms. There then occurs an acute ascending motor paralysis usually with retention of sphincteric functions and variable sensory loss. Typically muscular weakness begins in the feet and legs, more or less symmetrically, and progresses in a symmetrical fashion over a period of days in an ascending fashion to involve upper legs, arms, respiratory, and cranial muscles. Tingling paresthesias may occur, and there is sometimes loss of position and vibration sense; but sensory loss is not a prominent feature of the typical syndrome. Treatment consists of supportive measures, particularly respiratory support, during a recovery of weeks to months, which is usually complete in the 90% who survive. Glucocorticoids have been used with variable results.