Most advice about probiotics is written for dogs, and cats are not small dogs. They're strict meat-eaters with shorter guts, they're far more sensitive to stress, and anyone who has tried to give a cat a tablet knows they have opinions. This guide covers what a probiotic can do for a cat, when it's worth trying, the signs that need a vet instead, and how to get one into a fussy eater.
This is general information. If your cat seems unwell, call your vet.
What a probiotic does for a cat
A cat's gut is home to a large community of bacteria that help digest food, keep harmful microbes in check and support the immune system. A probiotic adds more of the helpful kinds. A prebiotic is a fibre that feeds them. When this community is disturbed, by a change of food, stress or antibiotics, the result is often soft stools, gas or a fussy appetite. Probiotics are well studied in cats. In one study of shelter cats, those given a probiotic had fewer long-lasting bouts of diarrhoea than those that weren't.
When a probiotic can help
- Stress. Cats react strongly to change, such as moving house, a new pet or baby, boarding, travel, vet visits and festival noise. A stressed cat often gets an upset tummy.
- Changing food. Moving between brands, or between dry and wet food or home-cooked meals.
- During and after antibiotics. Antibiotics kill helpful bacteria along with harmful ones. Ask your vet about timing.
- Everyday upkeep for cats that tend toward soft or very smelly stools, once a vet has ruled out other causes.
When to see a vet instead
Cats hide illness well, so take these seriously:
- Not eating for more than a day. Cats, especially overweight ones, can develop a serious liver problem (hepatic lipidosis) if they stop eating, even for a few days.
- Straining in the litter box. It can look like constipation, but in male cats especially it can mean a blocked bladder, which is an emergency. If your cat is straining and little or nothing comes out, go to a vet immediately.
- A kitten with diarrhoea, or any unvaccinated cat with diarrhoea and vomiting. Feline panleukopenia (similar to parvovirus in dogs) and parasites are serious in young cats.
- Blood in the stool, black stool, repeated vomiting, or weight loss.
- Hiding, lethargy or a cat that seems "not themselves" along with tummy trouble.
- Diarrhoea lasting more than 48 hours.
A probiotic supports a healthy gut. It doesn't treat infections, parasites or any of the problems above.
What about curd or yogurt?
Many adult cats don't digest lactose well, so dairy can cause the very loose stools you're trying to fix. Curd also contains a smaller and less predictable number of cultures than a measured supplement. A lick of plain curd as an occasional treat is fine if your cat tolerates it, but it isn't a reliable probiotic.
Choosing a probiotic for your cat
- A dose for cats, by weight. Cats need much smaller amounts than dogs. The label should say how much to give a 3 kg cat and a 5 kg cat.
- A clear culture count, with its unit. Check whether it's per gram, per serving or per pack.
- A prebiotic, such as FOS, to feed the cultures.
- A form your cat will actually eat. For most cats, a fine powder mixed into food is far easier than a capsule.
- Allergens, if your cat has known sensitivities.
- Taurine is a useful extra. Cats can't make enough of it themselves and must get it from food.
How to get a fussy cat to take it
- Use wet food if you can. Powders mix in far better than with dry kibble.
- Start small. Mix the powder into a spoonful of your cat's favourite food and offer that first, before the rest of the meal, so the whole dose is eaten.
- Build up slowly. Begin with a quarter of the dose and increase over four or five days. This also gives the gut time to adjust.
- Don't mix it into hot food. Heat can harm live cultures. Let the food cool to room temperature first.
- Don't add it to the water bowl. You can't tell how much your cat has taken, and it can put them off drinking.
Quick answers
Can I give my cat a dog probiotic?
Only if the product gives a dose for cats. Many dog products are dosed for much larger animals. A product made for both species, with a separate cat dose, is fine.
Can kittens have probiotics?
Some products are suitable from about one month old, at a reduced dose. If a kitten has diarrhoea, though, see a vet first. Kittens dehydrate quickly.
How long until a probiotic works in cats?
Stools often improve within one to two weeks. If nothing changes after a month, talk to your vet.
Are there side effects?
Some cats have slightly softer stools or a little gas for the first few days. Starting with a small amount and building up usually avoids this.
A note from us
We make Cani-Gut, a pre- and probiotic powder for dogs and cats. For adult cats, the dose is 2 g per 5 kg of body weight, up to 5 g a day, and 1 g per 5 kg for kittens from one to three months. It's a fine powder that mixes into wet food, and it contains taurine, prebiotic fibre and digestive enzymes alongside the cultures. It contains soy. It isn't a treatment for any of the warning signs above. If your cat is unwell, see your vet first.
