Seeing your dog be sick or pass loose stools can make your stomach drop too. A single mild episode in an otherwise bright adult dog is not always an emergency, but vomiting and diarrhoea can also be signs that need prompt veterinary advice.
The useful question is not “what caused it?” from your kitchen floor. It is “how is my dog now, and are there any warning signs?” This guide helps you make that call. It cannot diagnose your dog or replace advice from your own vet.
Quick answer
- Contact your vet promptly if vomiting or diarrhoea is repeated, severe, lasting more than 24 hours, or comes with other changes such as blood, pain, low energy or reduced appetite.
- Seek urgent veterinary advice for repeated unproductive retching, a swollen abdomen, collapse, breathing difficulty, seizures, suspected poisoning or a dog who cannot keep water down.
- Puppies, older dogs and dogs with an existing condition, medication or a prescribed diet need a lower threshold for a call.
- Do not give human medicines or try to make your dog vomit unless a vet tells you to.
When should I call the vet?
Call your veterinary practice for advice as soon as possible if the vomiting or diarrhoea is more than a brief, mild episode, or if your dog seems unlike themselves. You know their normal behaviour better than anyone.
Contact your vet promptly if you notice any of these:
- vomiting more than once, repeated diarrhoea, or symptoms continuing for more than 24 hours
- blood in vomit or poo, black tar-like poo, or diarrhoea that is very watery or constant
- reduced appetite, refusing water, obvious thirst changes, or trouble keeping water down
- lethargy, weakness, pain, a tense tummy, restlessness or a change in usual behaviour
- a puppy, an older dog, or a dog with an ongoing condition, medication or prescribed veterinary diet
- possible scavenging, a swallowed object, a toxin, or a sudden change after an outing
This is not a checklist for working out a cause. Different problems can look alike at home, and a vet can decide what information matters most for your individual dog.
Signs that need urgent help now
Phone your vet or their out-of-hours service without delay if your dog has any of the following:
- repeated retching with little or nothing coming up
- a suddenly swollen, hard or painful-looking abdomen
- collapse, marked weakness, difficulty breathing, seizures or severe pain
- blood in vomit, or large amounts of blood in their poo
- suspected poisoning or a known swallowed item
- ongoing vomiting with an inability to keep water down
Do not wait to see whether these signs settle overnight. Call first so the practice can tell you where to go and what to do next.
What can I safely do while I make the call?
Keep things calm and gather the useful facts. If your dog is comfortable, offer access to fresh water. Do not force food or water, and do not give medicines from your own cupboard unless a vet has specifically advised it.
Before you ring, note:
- when the first episode happened and how often it has happened since
- what the vomit or poo looked like, including any blood or unusual material
- whether your dog is eating, drinking, urinating and behaving normally
- anything they may have eaten, chewed, scavenged or had access to
- any medication, ongoing condition or prescribed diet
- their age, and whether other pets in the household are unwell
If it is safe to do so, a photo of the vomit or poo, the packaging of a suspected item, or a small fresh poo sample can be useful. Your vet will tell you whether to bring anything in.
A brief mild upset versus a dog who is unwell
Sometimes an adult dog has a short-lived tummy upset and otherwise remains bright, comfortable and interested in normal life. PDSA notes that mild diarrhoea for less than 24 hours in an otherwise well dog may be suitable to monitor with veterinary advice if needed.
That is not a reason to wait if your dog is deteriorating, vulnerable or showing any red flag above. In particular, puppies can become dehydrated more quickly, and older dogs or dogs with health conditions may have less room for a “let’s see how they are tomorrow” approach.
What not to do
- Do not try to diagnose the cause from one sign alone.
- Do not give human anti-sickness, anti-diarrhoea or pain medicines.
- Do not try to make your dog vomit unless a vet tells you to.
- Do not assume a “natural” food, treat or supplement is appropriate for a dog who is unwell.
- Do not delay a call because you are worried about seeming over-cautious. Your vet would rather help you decide what is needed.
A practical call checklist
- Check your dog’s breathing, alertness and comfort.
- Look for blood, repeated vomiting, severe diarrhoea, a swollen abdomen or collapse.
- Think about their age, existing conditions, medication and anything they may have eaten.
- Phone your veterinary practice and describe what you have seen.
- Follow their instructions, including where to go if the practice is closed.
The bottom line
Vomiting and diarrhoea are common, but they are not a diagnosis. A mild, short-lived episode in a well adult dog may be one thing. Repeated signs, blood, pain, lethargy, dehydration risk or a vulnerable dog are another. When you are unsure, call your vet and let them help you judge the next step.
Reviewed: 27 July 2026.
