Background and purpose: Guillain-Barré syndrome (GBS) is an infrequent, but potentially life-threatening disease with possible dysautonomic features and respiratory failure as potential complications. There are only a few previous studies on GBS in Norway. For this reason we did a thirteen year retrospective study including all patients treated for GBS in the Medical Intensive Care Unit (MICU), with focus on presence of antecedent infection, presenting clinical features symptoms, diagnostic tools, treatment and complications. Methods: This study included all patients with GBS admitted to the MICU at Oslo University Hospital, Ulleval, from the beginning of 2000 until the end of 2013. Results: A total of 32 patients were included. Antecedent infection was detected in over half of our patients, with upper airway infection being the most common. The most frequently presenting symptom in our patients was progressive muscle weakness, typically in a symmetrical, distal to proximal fashion. Over half of our patients had mild sensory disturbances. Signs of dysautonomia were present in over half of our patients. Spinal protein was ultimately found to be increased in 91 % of our patients after recurrent lumbar punctions. Respiratory failure occurred in 41 % of our patients. Complications (especially pneumonia) were almost twice as common in the patient group requiring mechanical ventilation. All patients received treatment with either plasmapheresis or immunoglobulins intravenously (IVIg), sometimes both. IVIg seemed to be first choice in most cases. Conclusions: The primary reason for MICU admission was observation. Almost half of our patients required mechanical ventilation (MV). The most frequent complication in the MICU was pneumonia, which was strongly associated with MV.