Patients with autonomic neuropathy may experience a number of symptoms related to their condition. Symptoms may be mild to severe and can vary from person to person, depending on which nerves are damaged.

One of the most common groups of symptoms associated with autonomic neuropathy results from damage to nerves that affect blood vessels. People who have damage to these nerves may experience blood pressure and body temperature abnormalities. For example, patients may experience a rapid drop in blood pressure upon standing (orthostatic hypotension), which can lead to dizziness and fainting. Furthermore, some patients may find that their heart rate does not adjust appropriately during physical exertion. High blood pressure can also result from damage to the nerves that supply blood vessels. 

Additionally, if blood vessels of the skin are not able to dilate effectively to reduce body heat, it can result in a reduced ability to sweat, which can lead to overheating and heat stroke. In some cases, ANS nerve damage may cause extreme sweating at night or while eating.

Additional symptoms associated with autonomic neuropathy include:

• Bladder and bowel dysfunction. People with autonomic neuropathy may experience difficulty emptying their bladder (urinating) or bowel (defecating). This may lead to conditions such as urinary tract infections and urinary or fecal incontinence.
  
  
• Sexual problems. Men may experience impotence, while women may experience vaginal dryness and difficulties becoming aroused or achieving orgasm.
  
  
• Gastrointestinal problems. A wide range of symptoms can result from nerve damage to the gastrointestinal system, including symptoms associated with gastroparesis (delayed gastric emptying). Symptoms may include constipation, nausea, vomiting, abdominal bloating, loss of appetite and early satiety (feeling of fullness). Other parts of the gastrointestinal system may also be damaged. For example, nerve damage affecting the esophagus may cause difficulty swallowing and nerve damage affecting the intestines may cause diarrhea.
  
  
• Lack of indicators of hypoglycemia (low blood sugar). Patients may not display the signs that typically accompany this condition, such as shakiness, sweating and palpitations. In people who have diabetes, this may make the condition difficult to manage.
  
  
• Poor performance of the pupils in the eye. Pupils may react sluggishly to changes in light or dark.

Symptoms of autonomic neuropathy may be uncomfortable, but are rarely life-threatening.