How is constipation evaluated?
Most people do not need extensive testing to evaluate constipation. Only a small number of patients with constipation have a serious underlying medical problem (such as poor function of the thyroid gland, diabetes, or colorectal cancer).
If you have constipation that has persisted for more than two weeks, you should see a doctor to determine if you need further evaluation. For a patient who has colorectal cancer, early detection and treatment may be life-saving.
Standard evaluation for constipation includes performing blood tests and examining the colon by colonoscopy, particularly for patients older than 50 years.. Other tests include colonic transit studies (time it takes for stools to move through the colon) and anal manometry (measures pressure and muscle function in the rectum and anus).
Most patients with serious constipation, and without any obvious illness to explain their symptoms, suffer from one of two problems:
- Colonic inertia (also called lazy colon): a condition in which the colon contracts poorly and retains stool. This can be determined by colon transit studies.
- Obstructed defecation: a condition in which the colon contracts normally, but the patient is unable to expel stool from the rectum. This condition can be confirmed by a test called anal manometry.
When should I call my healthcare provider?
Call your healthcare provider if:
- Constipation is a new problem for you.
- You have blood in your stool.
- You are losing weight unintentionally.
- You have severe pain with bowel movements.
- Your constipation has lasted more than three weeks.