Symptoms of Guillain-Barré syndrome vary from person to person and may be mild or severe. Most often, the first obvious symptom is weakness, and most often the weakness is felt in both legs. Over time, the weakness often involves the arms or head, affecting eye and head movement and speech. Occasionally, the weakness will affect the arms or muscles of the head before affecting the legs.
Sometimes the weakness is preceded or accompanied by a sensation of tingling, most often in the lower legs and feet. With each muscle group affected, there also can be pain and/or tingling. Guillain-Barré syndrome can temporarily impair the body's control of blood pressure, leading to dangerously low blood pressure when the person rises to stand after lying down or sitting.
The disorder progresses quickly, with most patients experiencing the worst weakness of legs, arms, chest and other muscle groups within three weeks of the start of the disease. In some cases, the weakness may worsen very rapidly. When this happens, weakness in the legs can become complete paralysis of the legs, arms and muscles of breathing over the course of hours or a few days. For that reason, a person who develops sudden weakness in the legs or arms should contact a doctor immediately.
The weakness may last days, weeks or months before sensation begins to return. Returning to pre-illness strength and functioning can take months or years. Most patients return to normal within months.