The plateau phase can take between two days and six months, but the most common duration is a week. Pain-related symptoms affect more than half, and include back pain, painful tingling, muscle pain, and pain in the head and neck relating to irritation of the lining of the brain.Many people with Guillain–Barré syndrome have experienced the signs and symptoms of an infection in the 3–6 weeks before the onset of the neurological symptoms. This may consist of upper respiratory tract infection (rhinitis, sore throat), or diarrhea. In children, particularly those younger than six years old, the diagnosis can be difficult and the condition is often initially mistaken (sometimes for up to two weeks) for other causes of pains and difficulty walking, such as viral infections, or bone and joint problems.On neurological examination, characteristic features are the reduced strength of muscles and reduced or absent tendon reflexes (hypo- or areflexia, respectively). However, a small proportion have normal reflexes in affected limbs before developing areflexia, and some may have exaggerated reflexes. In the Miller Fisher variant of Guillain–Barré syndrome (see below), a triad of weakness of the eye muscles, abnormalities in coordination, as well as absent reflexes can be found. The level of consciousness is normally unaffected in Guillain–Barré syndrome, but the Bickerstaff brainstem encephalitis subtype may feature drowsiness, sleepiness, or coma. Respiratory failure
A quarter of all people with Guillain–Barré syndrome develop weakness of the breathing muscles leading to respiratory failure, the inability to breathe adequately to maintain healthy levels of oxygen, and/or carbon dioxide in the blood.
IVIG works as well as plasmapheresis when started within two weeks of the onset of symptoms, and has fewer complications. IVIG is usually used first because of its ease of administration and safety; the risks include occasionally causing liver inflammation, or in rare cases, kidney failure. Glucocorticoids alone have not been found to be effective in speeding recovery and could potentially delay recovery. Respiratory failure
Respiratory failure may require intubation of the trachea and breathing support through mechanical ventilation, generally on an intensive care unit. The need for ventilatory support can be anticipated by measurement of two spirometry-based breathing tests: the forced vital capacity (FVC) and the negative inspiratory force (NIF). An FVC of less than 15 mL per kilogram body weight or an NIF of less than 60 cmH2O are considered markers of severe respiratory failure. Pain
While pain is common in people with Guillain–Barré syndrome, studies comparing different types of pain medication are insufficient to make a recommendation as to which should be used. Rehabilitation
Following the acute phase, around 40% of people require intensive rehabilitation with the help of a multidisciplinary team to focus on improving activities of daily living (ADLs). Studies into the subject have been limited, but it is likely that intensive rehabilitation improves long-term symptoms. Teams may include physical therapists, occupational therapists, speech language pathologists, social workers, psychologists, other allied health professionals and nurses.