For most people, chronic constipation can usually be managed with self-help measures and medications.
Rarely, chronic constipation may be a side effect of another condition (secondary constipation). Conditions that may cause secondary constipation include:
- Diseases of the colon (stricture, cancer)
- Metabolic disturbances (hypercalcemia, hypothyroidism, diabetes)
- Neurological disorders (parkinsonism, spinal cord lesions)
These disorders can often be diagnosed by blood tests or other diagnostic tests.
If chronic constipation cannot be effectively managed with self-help and medications, and other underlying diseases have been ruled out, the most common causes of chronic constipation are:
- Pelvic floor dysfunction. Pelvic floor dysfunction occurs when the muscles that usually relax during a bowel movement (external anal sphincter and puborectalis muscles) don't relax correctly, making it difficult to eliminate stool from the rectum, or when muscles are too lax (descending perineum syndrome).
- Slow-transit constipation (colonic dysmotility). This type of severe constipation generally occurs when colonic nerves or muscles don't work the way they should, so material takes much longer than usual to pass through the colon.