Megacolon is a condition of extreme dilation and poor motility of the colon, usually combined with accumulation of fecal material and the inability to evacuate it. The majority of cases (62 percent) are “primary” or “idiopathic,” which means there is no obvious reason for the condition. Some cases are “secondary,” meaning that something has interfered with normal defecation for a prolonged period of time, causing chronic constipation, with megacolon occurring as a sequela. Recent studies have shown that cats with idiopathic megacolon have a defect in the ability of the muscle in the colon to contract.

Megacolon can occur in any age, breed, or sex of cat, however, most cases are seen in middle aged cats (average age is 5.8 years). Most cases are in males (70 percent males, 30 percent females). Megacolon can be a frustrating and difficult condition.

Diagnosis and Treatment Notes:

  • Megacolon is generally diagnosed by history, physical examination and abdominal x-rays. Bloodwork, ultrasound and colonoscopy may be recommended.
  • Treatment depends on the severity of the disease, your individual pet, and your veterinarian. The majority of cats with megacolon are treated with high fiber diets, laxatives and enemas. In some cases, drugs that increase colon contractions or surgery may be necessary.  Discuss treatment details when your pet is diagnosed with this condition.


What to Watch for*:  

  • Decreased or absent defecation
  • Painful defecation
  • Multiple, unproductive efforts to defecate
  • Dry, hard feces

*Please notify us if you notice any of the above signs or if you have any questions!