Dog diarrhoea – when should I see a vet?

Updated 2026-09-30 · 1 sources

Based on: PDSA

Book a vet visit

This is not usually an emergency on its own – contact your vet if it lasts, gets worse or your dog seems unwell in any other way. It can have many causes, including a sudden change in diet, eating something that upsets your dog's tummy, worms and other gut parasites.

When to contact a vet What to do now

Contact a vet if you see any of this

Diarrhoea ongoing for more than 24 hours
Blood or mucus in the diarrhoea
Severe or constant watery diarrhoea
Reduced appetite
Vomiting
Lethargy or low energy
A painful stomach
Your dog seems unwell, is very young or very old, has an underlying health condition, or is taking medication

What you can do now

Note when it started, how often it happens and what else you see.
Take a photo or short video to show your vet.
Keep fresh water available.
Let your dog rest somewhere calm.

Don't

Do not give any human medicine.
Do not wait if it gets worse.

What it can mean

There are many different things that can cause diarrhoea in dogs.^[1] Most cases are mild and resolve within 24-48 hours.^[1] Some cases are more serious and require veterinary attention.^[1]

Other signs that can come with it

Soft, liquid or watery stools
Stools lighter or darker than usual
Straining to pass faeces
Passing faeces more often than normal
Going outside more regularly than usual
A dirty, smelly bottom
Gurgling stomach noises
Farting more than usual

Possible causes

A sudden change in diet
Eating something that upsets their tummy
Worms
Other gut parasites, such as giardia, cryptosporidium and tritrichomonas
Pancreatitis
Gut infections, such as Salmonella and Campylobacter
Poisoning or toxins
Inflammatory bowel disease
A gut blockage
Liver disease, kidney disease or cancer

What the experts say

“Overview. There are many different things that can cause diarrhoea in dogs and puppies. Fortunately, most cases are mild and resolve within 24-48 hours, but it’s important to be aware that some are more serious and require veterinary attention.”
— PDSA [1]

If your pet is struggling to breathe, has collapsed, is having a seizure or can't stand up: go to the nearest vet now.

Not sure how serious it is?

OkPaw asks a few quick questions about your pet and tells you in 30 seconds whether it can wait. Free on Google Play for Android.

OkPaw is on Android now – an iPhone version is on its way.

Common questions

How long do most cases last?

Most cases are mild and resolve within 24-48 hours.^[1]

When should I contact my vet?

Contact your vet for advice as soon as possible if it has been ongoing for more than 24 hours, your dog seems unwell, or there is blood or mucus in the diarrhoea.^[1]

What other signs can mean vet advice?

Reduced appetite, vomiting, lethargy and a painful stomach are reasons to contact your vet.^[1]

Sources

PDSA

How this page was made: written with the help of AI from the sources below, then checked claim by claim against those sources. Urgency levels follow OkPaw’s fixed safety rules. It is guidance, not a diagnosis. How we write our pages

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