Megacolon

What is Megacolon?
Dogs with megacolon have a large intestine (colon) with an abnormally increased diameter. The condition can be acquired from chronic retention of feces, essentially stretching the walls of the colon. The enlarged colon cannot properly move feces, leading to constipation and blockage. The longer the stool stays in the colon, the more moisture is taken from it, making it harder and even more difficult to move, and stretching the colon further.

How does my dog get Megacolon?
Anything that prevents your dog from defecating as often as he should can cause fecal material to stay in the colon too long, become hardened, build up and stretch the colon walls. These causes can be behavioral (reluctance to defecate in a strange place, such as when being boarded), traumatic (pelvic fractures), or due to debilitating illness that makes defecation difficult.

How do I know if my dog has Megacolon?
Affected dogs do not defecate as often as they should, and when they try, they will strain, often unproductively. Any stools produced are usually abnormally hard and dry. Some diarrhea, which may seep around the edges of the impacted mass, may be produced. The dog may become depressed and may vomit. This is a chronic condition that tends to worsen with time. Your veterinarian will carefully feel your dog's bowel through his abdomen to tell if it is abnormally full. She will also do a rectal examination, and may examine the bladder and urine in case that is the root of the problem. She will check for dehydration. She will take radiographs and perhaps ultrasound of the intestinal area, both of which will show the packed colon. Ultrasound or colonoscopy are superior for determining some possible causes.

What can I do about Megacolon?
Your veterinarian may administer intravenous fluids to correct any dehydration. Your dog may have to be anesthetized to remove the impacted material, which will be done using warm water enemas, gels, and either gloved fingers or forceps.  In severe cases, surgery may be necessary. Any underlying causes will need to be corrected as much as possible. Your veterinarian will probably prescribe stool softeners and a drug to improve colon motility. Your dog will be put on a special diet that does not form a lot of bulk. Exercise may improve his intestinal motility. NOTE: Do not be tempted to try enemas at home without advice from your veterinarian.  Sodium phosphate retention enemas (such as Fleet) can cause problems with dogs.

Is there anything I can do to prevent my dog from getting Megacolon?
If your dog isn't defecating as he should be, don't adopt a wait and see attitude. The longer he has impacted feces in him, the worse the condition will get. See your veterinarian if there are any changes in your dog’s defecation habits.

Are there certain breeds that get Megacolon more often?
The condition appears to occur equally in all breeds