Autoimmune Autonomic Ganglionopathy (AAG)

What it is: Autoimmune Autonomic Ganglionopathy (AAG) is a very rare disorder in which the body’s immune system attacks the autonomic ganglia—the nerve centers that help control automatic body functions such as blood pressure, heart rate, digestion, and sweating. 

Symptoms can develop suddenly (over days to weeks) or more gradually, and the condition can range from mild to severe. In many cases, AAG is associated with antibodies that disrupt communication within the autonomic nervous system.

Familial Autoimmune Autonomic Ganglionopathy includes similar symptoms and suggests a genetic or shared predisposition within families.

Key Symptoms

  • Severe dizziness or fainting when standing, due to low blood pressure.
  • Feeling like their body can’t properly regulate heart rate or blood pressure.
  • Dry mouth and dry eyes, sometimes needing to drink water constantly.
  • Difficulty with digestion, including constipation, bloating, or feeling full quickly.
  • Problems with urination (trouble starting, incomplete emptying, or retention).
  • Abnormal sweating—either too little (dry skin, heat intolerance) or too much.
  • Blurred vision or trouble adjusting to light due to pupil dysfunction.
  • Sudden onset of widespread symptoms that may feel overwhelming or unexplained.

Patients often describe a sense that their “automatic functions aren’t working right,” with symptoms affecting multiple body systems at once.