Tummy upsets in cats and dogs

Understanding possible causes and treatment

Cats and dogs can get upset tummies resulting in vomiting, diarrhoea or both, for a variety of different reasons.

In dogs, vomiting and diarrhoea can be brought on by a sudden change in diet, stealing food they shouldn't or eating too much too quickly. These will usually clear up in time by themselves but sometimes the reason can be more serious like an infection, eating a foreign body like a sock or toy, parasites, ingesting a poison or toxin or a medical condition such as kidney or liver disease.

If your dog is being sick or having diarrhoea, first of all think about the history of the last few days, have they eaten anything poisonous?

Are you missing any toys or objects they like to play with? Did you see them with anything toxic like chocolate or plant material in their mouth?

Also consider the age and health of your pet, have they been showing other signs of illness like losing weight or inappetance? If any of these are relevant then you should contact your vet as soon as possible. 


If your dog is still bright and well, but vomiting occasionally, then withhold food for 24 hours, (or for puppies under 6 months old, only 6 hours) they can have access to water but only a small amounts often so they don't bring it back up again. After 24 hours (or 6 hours for puppies aged under 6 months) they can be fed a bland diet, something like chicken and rice, small amounts fed little and often throughout the day. If vomiting continues or starts again then seek veterinary attention.

After 2-3 days on a bland diet their normal food can be reintroduced gradually. If your dog isn't vomiting but has diarrhoea then there is no need to starve them and a bland diet can be introduced little and often right away.

In cats there also can be many reasons for vomiting and diarrhoea. It could be a diet change, parasites, infections, toxins or a medical condition. It’s important to think of the overall health of your cat as if they aren't eating or drinking for 24 hours they can become very ill.

Are they lethargic? Are they on medication that could be affecting them? Are they young and therefore small and likely to be dehydrated quickly? Or if they are older could they have lost weight and may have underlying health problems? If any of these are likely then contact your vet as soon as possible.

If your cat is well and bright and having occasional vomiting and diarrhoea then food can be withheld for 12 hours. (for Kittens up to 4 hours) but water can be available. After this time, a bland protein only diet can be introduced something like plain cooked chicken or white fish and fed little and often. You can also water down the food a little to help with hydration as cats a prone to not drinking. After 2-3 days their usual food can be gradually reintroduced. If your cat continues vomiting or it starts again then seek veterinary attention.

If your cat isn't vomiting but has diarrhoea then there is no need to withhold food.

It’s important to recognise if your pet is unwell, quiet, lethargic or showing signs or dehydration, if they are passing black tar-like faeces, vomiting blood or dark coffee-coloured vomit then you should contact your vet as soon as possible.

Also, for any young puppies and kittens that have had vomiting or diarrhoea longer than 24 hours, you should seek veterinary advice.

If your pet is unwell and you would like more advice please contact the Pet Health Helpline on 03333321947.

Vet nurses are on hand to answer your queries 24 hours a day, 7 days a week.