pathophysiology
Last reviewed 10/2023
In most cases of constipation, there are a combination of aetiological factors responsible. Commonly, the mixture is of a low fibre diet, not drinking enough fluids, inactivity, obesity, and a persistent failure to respond to the urge to defaecate.
Other factors such as the long term use of purgatives can cause constipation by rendering the bowel atonic - this may be temporary or permanent.
Drugs such as codeine and opiates slow gut motility and so may cause constipation. Other drugs, such as aluminium hydroxide and iron, solidify the stool and so can cause constipation.
Endocrine and metabolic disturbances such as hypothyroidism and hypercalcaemia may cause constipation.