The autonomic nervous system regulates the functions of the intestines. Nerve damage of the intestines can cause diarrhoea or constipation. On the other hand, both diarrhoea and constipation are very common problems caused by many different reasons. Diabetes medication, especially metformin, can also cause stomach issues. Other common causes are ruled out by basic examinations.
Potential anaemia as a sign of intestinal haemorrhage, blood inflammation levels, hypothyroidism, lactose intolerance or coeliac disease can be established with laboratory tests. Stool samples can be used to examine potential intestinal haemorrhage, the operation of pancreatic enzymes or a gut infection. Other possible options include contrast radiography and colonoscopy.
Based on the symptoms, nerve damage-related diarrhoea can be treated with psyllium or, if necessary, loperamide or codeine products. Constipation is treated with normal constipation medicines or laxatives.