Roundworms That Cause Intestinal Obstruction in Cats

A cat with roundworms may not exhibit any signs at all.
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Various parasites have their sights set on taking up residence in or on your cat, and one common unwelcome guest is the roundworm. This long, spaghettilike parasite makes itself at home in your cat's intestines, leeching nutrients from her system and sometimes causing a blockage due to high numbers.


Every worm starts as a tiny egg that must spend time in a cat's system to fully mature. Your cat can become infected one of three ways: through drinking the milk of an infected mother, by eating an infected prey animal or by direct ingestion through grooming after walking in tainted soil or infected cat poop. Once ingested, the egg hatches in the intestines and the worm larvae does some traveling through your cat's other organs before settling back down in her intestines. There it will begin feeding and reproducing.


The frustrating part about a roundworm infestation is that in most cases you will not know your cat is playing host to these parasites. Small infestations may go unnoticed for weeks or months. As the population grows and steals more and more nutrients from your cat's system, you may notice diarrhea, vomiting and a negative change in her coat. Sometimes you will find live, squirming worms in your cat's vomit, indicating a heavy infestation.

Intestinal Blockage

In some cases, your cat may take on a pot-bellied appearance or experience pain and discomfort in her abdomen. This occurs if the population grows too large and the worms jockey for position in their ill-gotten home. They become intertwined and essentially create a writhing knot in your cat's intestines. At this stage, the worms have gone from disgusting and annoying freeloaders to life-threatening trespassers. Delayed treatment could spell doom for your cat.


Fortunately, roundworms react very well to deworming medications, meaning they die quickly and leave your cat in peace. Once the medication takes effect, the worms die and and the cat passed them as he visits the litter box. Roundworm knots that cause intestinal blockage may need to be removed surgically, as the mass of worms may be too large and too solid to thoroughly kill and pass safely. See your vet if you suspect your cat has roundworms, so he can ascertain the extent of the infestation and the proper course of action for treatment.

Always check with your veterinarian before changing your pet’s diet, medication, or physical activity routines. This information is not a substitute for a vet’s opinion.

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