Common Causes of Diarrhoea in Cats

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If your cat has diarrhoea, it’s unpleasant for you to deal with, but even more unpleasant for your cat. There are a number of possible causes for a bout of feline diarrhoea, and it may be something as simple as a change in food upsetting his stomach, or it may be a sign of a more serious illness. If your cat suffers from diarrhoea that doesn’t immediately clear up, it’s essential to get him checked out by your vet.

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Causes of Diarrhoea in Cats

Giardiasis – Giardia is an intestinal parasite that your cat can pick up from an infected cat’s faeces or by drinking water that’s contaminated with the organisms. The diarrhoea that’s caused by having giardiasis smells particularly foul, and appears foamy and greasy, so you’ll know straight away that there’s something wrong.
Parasites – There are a number of other types of feline intestinal parasites that could be the cause of your cat’s diarrhoea, such as tapeworms, roundworms and coccidia. As well as diarrhoea, symptoms will probably include listlessness, loss of appetite and a generally being ‘under the weather’.
Eating non-food items – If your cat has pica, a condition where he likes to chew and eat non-food items like wool or rubber, or if he’s just not fussy about what he puts in his mouth, diarrhoea could be the result. If it’s a one-off and he hasn’t eaten something poisonous, it should clear up pretty quickly on its own.

IBD – Inflammatory Bowel Disease, or IBD, causes a cat’s stomach to become less efficient at absorbing the nutrients from his food, and diarrhoea is one of the main symptoms. It’s essential that you visit your vet if you suspect your cat may have IBD, as medication is required to manage the illness.
Bacterial infection – Another cause of your cat’s diarrhoea could be a bacterial infection, such as salmonella, campylobacter or e.coli, which should be treated with antibiotics to avoid the possibility of septicaemia.
Viral infection – Viral infections like FIV, FelV and feline distemper can also cause diarrhoea in cats as part of the overall illness.

Liver disease – If your cat has liver disease, it can affect many different areas of his body, including his gastrointestinal system, so vomiting and diarrhoea could be a sign of this.
Hyperthyroidism – Hyperthyroidism affects all of a cat’s organs by over-stimulating them, meaning that the bowels become much more active. If you notice your cat has regular, severe and smelly diarrhoea, your vet can test for hyperthyroidism.
Cancer – If your beloved cat has cancer, you may notice a wide variety of upsetting symptoms, including diarrhoea. The most common type of cancer that can cause problems with your cat’s bowel movements is lymphoma, which commonly develops in a cat’s intestinal system.

What to do if Your Cat has Diarrhoea

Bouts of mild diarrhoea aren’t that uncommon in cats, so unless it’s severe or you see any other troubling symptoms you can usually wait 12-24 hours to see if it clears up on its own. During this time it’s best to remove access to food, but be sure to leave plenty of fresh water out to avoid your cat getting dehydrated.

After your cat has fasted for a few days try introducing a bland diet for a further few days such as chicken and rice which will usually help to settle the digestive tract. You can also give him a small amount of Lactobacillus plain unsweetened yoghurt or powder, which can be helpful after a bout of diarrhoea to replace good bacteria, and especially after a course of antibiotics.