Guillain-Barre syndrome (GBS)

Guillain-Barre syndrome is an acute condition in which the immune system attacks the peripheral nerves, the nerves outside the brain and spinal cord. It's usually preceded by an infection, often by one to two weeks, and current understanding is that antibodies produced against the infectious trigger cross-react with components of the nerve, damaging the myelin coating or the nerve fibers themselves. The classic demyelinating form accounts for the large majority of cases in Western countries, while axonal forms are more common in parts of Asia and Central and South America.

GBS is described as a rare condition and the leading cause of acute paralytic neuropathy worldwide, with incidence varying by region and the infections circulating locally. Unlike most conditions here, it's usually a single, self-limited illness rather than a lifelong one.

Common signs

Weakness and tingling that usually begin in the feet and legs and move upward, often fairly symmetrically, with loss of reflexes. It can progress over hours to days to weakness of the arms, face, and the muscles used for breathing and swallowing. Because it can affect breathing and heart rate and blood pressure, it's treated as a medical emergency.

This is a plain-language summary for orientation, not a diagnosis. Mechanisms are described as current understanding, not settled fact. Work with your own clinician for your care.