Megacolon and chronic constipation in cats
Also known as Chronic constipation, Obstipation.
The colon widens and loses strength, and faeces build up and harden. It is more common in older or dehydrated cats and in those with pelvic or spinal injuries.
If it has not passed faeces for more than 48–72 hours or is vomiting, see the vet.
- System
- Digestive system
- Is it urgent?
- Not usually
- Spreads to other cats
- No
- Spreads to people
- No
- Typical cost in Spain
- Consultation and X-ray, €80–180; emptying under sedation, €200–500; surgery, €1,200–2,500.
Symptoms
- Passes faeces rarely and with a lot of straining
- Small, hard, dry faeces
- Vomiting
- Loss of appetite
- Sometimes a little liquid, which is mistaken for diarrhoea
Causes
Idiopathic in many cases; dehydration from kidney disease, old pelvic fractures, spinal cord problems in the Manx and Cymric, and osteoarthritis that makes the cat avoid the litter tray.
How it is diagnosed
Palpation, X-rays and blood tests to look for the cause.
Treatment
Hydration, a high-fibre or highly digestible diet, laxatives and prokinetics prescribed by the vet, and emptying the colon at the clinic if needed. In cases that do not respond, colon surgery.
No doses, on purpose: any medicine must be prescribed by your vet for your cat.
Prognosis
Good if treated early; surgery gives good results in cats that do not respond.
Prevention
Water and wet food, a healthy weight and a low-entry litter tray for older cats. Never use human pharmacy enemas: some are toxic to cats.
Breeds at higher risk
It is described more often in these breeds. That does not mean all of their cats will have it, nor that a moggy is free of it.
Frequently asked questions
What causes megacolon and chronic constipation?
Idiopathic in many cases; dehydration from kidney disease, old pelvic fractures, spinal cord problems in the Manx and Cymric, and osteoarthritis that makes the cat avoid the litter tray.
Can megacolon and chronic constipation be cured?
Good if treated early; surgery gives good results in cats that do not respond. Hydration, a high-fibre or highly digestible diet, laxatives and prokinetics prescribed by the vet, and emptying the colon at the clinic if needed. In cases that do not respond, colon surgery.
How much does it cost to treat megacolon and chronic constipation?
As a guide for Spain in 2026: Consultation and X-ray, €80–180; emptying under sedation, €200–500; surgery, €1,200–2,500. Prices vary a lot between clinics and cities, and out-of-hours emergencies cost more.
Which breeds are most at risk?
It is described more often in Manx and Cymric. That does not mean every cat of those breeds will have it, nor that a moggy is free of it.
More in digestive system
Educational content from Michipedia. It does not replace diagnosis or treatment by a vet: if you have any doubt about your cat's health, ask. Costs are a guide for Spain in 2026.