Vomiting and diarrhoea in dogs and cats: signs and when to get help

Vomiting is the forceful bringing up of material from a dog's stomach or upper intestine, usually with retching and visible effort from the abdomen.

Drooling, nausea and repeated swallowing may appear before it happens. The action and effort help distinguish vomiting from passive regurgitation, although a video can be useful when the difference is unclear. [1]

Vomiting usually involves nausea, retching and abdominal effort, while regurgitation is more passive and often brings up undigested food or fluid without heaving.

Regurgitated material can look tube-shaped because it has come from the oesophagus. The distinction matters because vomiting and regurgitation point the veterinary team towards different parts of the digestive system and different possible causes. [1]

Sudden vomiting can follow a dietary upset, overeating or motion sickness, but infection, parasites, pancreatitis, heatstroke, toxins, a blockage and liver or kidney disease are also possible.

The vomit's appearance cannot identify the cause by itself. What the dog may have eaten, the pattern of vomiting, other symptoms, age, medicines and examination findings all help narrow the possibilities. [2]

Yellow or greenish foam can be bile, a digestive fluid made by the liver and stored in the gallbladder, and it may appear when the stomach is empty.

Colour alone does not show why a dog vomited. Repeated episodes, pain, lethargy, a swollen abdomen, inability to keep water down or any other worrying change make the wider clinical picture more important than the colour. [2]

Fresh red blood or dark material resembling coffee grounds can indicate bleeding in the upper digestive tract and warrants urgent veterinary advice.

The amount and appearance do not reliably show how serious the cause is. Bleeding may occur alongside stomach irritation, ulceration, a foreign object, a toxin or another illness, so it needs clinical assessment rather than colour matching alone. [3]

Repeated vomiting needs urgent veterinary care when a dog cannot keep water down, seems weak or unusually quiet, has blood, severe diarrhoea, pain, breathing difficulty or another marked change.

Ongoing fluid loss can lead to dehydration and weakness, with puppies, older dogs and pets with other health problems at greater risk. Frequency matters, but the dog's overall condition matters just as much. [4]

Repeated unproductive retching, especially with a swollen abdomen, drooling, restlessness, pale gums, breathing difficulty or collapse, is an emergency: contact a veterinary service immediately.

This pattern can occur with gastric dilatation-volvulus, often called GDV or bloat, which can worsen rapidly. A dog's abdomen is not always visibly enlarged, particularly when the stomach sits beneath the ribcage. [5]

Suspected poisoning or a swallowed foreign object with vomiting is an emergency: contact a vet or emergency veterinary service immediately.

The veterinary team needs to know what may be involved, roughly when exposure happened and what signs are present. Vomiting does not prove the material has all left the body, and an obstruction can remain life-threatening. [6]

Vomiting removes fluid and salts before the body can use them, and repeated losses can leave a dog dehydrated and disturb its electrolyte balance.

A dog may also drink less because of nausea or bring water back up. Puppies, older dogs and dogs with kidney, heart or other health problems can have less reserve when fluid losses continue. [1]

A vet starts with the vomiting history and a physical examination, including the mouth and abdomen, while checking for pain, dehydration, bleeding and possible exposure to rubbish, poisons or unsuitable objects.

The next steps depend on those findings. Blood, urine or faecal tests and abdominal imaging may be considered when the history or examination suggests a blockage, toxin, body-wide illness or another significant cause. [1]

No. Vomiting by itself does not show that a dog needs an acid-suppressing medicine, and these medicines are not anti-sickness drugs.

They are aimed at acid-related injury in selected situations, such as documented or strongly suspected ulceration or oesophageal damage. The veterinary decision depends on the cause, bleeding risk and other findings rather than the presence of vomiting alone. [7]

Vomiting is the forceful bringing up of material from a cat's stomach or upper intestine, usually with retching and visible abdominal effort.

A cat may salivate, swallow repeatedly or show nausea beforehand. Those active movements help separate vomiting from regurgitation, while a video of the episode can help the veterinary team understand what happened. [8]

Vomiting usually includes nausea, retching and abdominal effort, whereas regurgitation is passive and often brings up undigested food or fluid without heaving.

Regurgitated material can be tube-shaped because it comes from the oesophagus. The difference is useful clinically because the two events involve different parts of the digestive tract and lead to different possible causes. [8]

A stomach upset, diet change, eating something unusual, worms, a hairball or travel sickness can cause vomiting, but pancreatitis, toxins, a blockage and kidney, liver or hormonal disease are also possible.

One episode cannot identify the cause. Age, appetite, drinking, urination, stool changes, possible exposures and whether the cat is otherwise bright or unwell give the symptom its clinical context. [9]

A nauseous cat may drool, lick its lips, turn away from food, eat less, swallow repeatedly or retch, even when no vomiting is seen.

Cats can show nausea subtly, so a change in their response to food may be more noticeable than obvious sickness. Appetite, posture, grooming and interaction can provide useful context alongside any digestive signs. [10]

No. Cats can vomit hairballs, but repeated vomiting can also come from stomach or intestinal disease, pancreatitis, toxins, a blockage or illness elsewhere in the body.

A hairball forms when swallowed fur collects in the stomach, yet fur in vomit does not rule out another problem. Frequency, appetite, weight, stool and general wellbeing help show whether more investigation is needed. [8]

A cat needs urgent veterinary advice when vomiting repeats, food or water will not stay down, or the cat is lethargic, painful, pale, weak or showing another worrying change.

Diarrhoea, blood in the vomit, altered drinking or urination and possible access to something unsuitable also raise concern. Kittens, older cats and cats with another illness can become unwell more quickly. [9]

Fresh blood or dark material resembling coffee grounds can indicate bleeding in a cat's upper digestive tract and warrants urgent veterinary assessment.

Its colour and amount cannot reliably identify the cause or severity. Stomach irritation, ulceration, a swallowed object, a toxin and other illnesses can produce bleeding, so the wider clinical picture needs assessing. [11]

Suspected poisoning or a swallowed foreign object with vomiting is an emergency: contact a vet or emergency veterinary service immediately.

String, thread and fabric can be especially hazardous because a long object may damage the intestine while part remains anchored. Vomiting does not prove the substance or object has safely left the body. [11]

Vomiting with breathing difficulty, collapse, unresponsiveness, severe weakness or pale, blue, grey or purple gums is an emergency requiring immediate veterinary care.

These signs can reflect shock, poor circulation, low oxygen or another life-threatening problem rather than a simple stomach upset. The emergency team can prepare for arrival when contacted while transport is being arranged. [4]

A vet combines the cat's history with a physical examination and considers appetite, weight, hydration, pain, stool, medicines, possible toxins and access to string or other objects.

Depending on the findings, blood, urine or faecal tests and abdominal x-rays or ultrasound may be useful. Persistent or severe cases sometimes need endoscopy and tissue samples to identify the underlying problem. [8]

Diarrhoea means a dog's stools are looser or more watery than normal, often with a change in how frequently or urgently the dog needs to pass them.

A single soft stool and repeated watery diarrhoea are not the same clinical picture. Colour, volume, blood or mucus, straining, vomiting, appetite and the dog's general behaviour all add useful context. [12]

Scavenging, gastroenteritis, another digestive disorder, a medicine reaction or a sudden diet change are common explanations for acute diarrhoea in UK dogs.

Parasites, infections, pancreatitis, toxins and intestinal blockage are among other possibilities. The same outward sign can arise in several ways, so recent food, rubbish, travel, contacts, medication and vaccination history can all matter. [13]

Fresh red blood or mucus can appear when the large intestine is inflamed, but it does not identify one cause or prove that the illness is bacterial.

The amount, frequency and dog's overall condition matter. Bloody diarrhoea with repeated vomiting, weakness, pain, pale gums, collapse or severe watery loss warrants urgent veterinary assessment. [12]

Black, tarry stool can be digested blood from bleeding in the stomach or small intestine and warrants urgent veterinary advice.

It is different from a naturally dark but normally formed stool. Medicines, foods and swallowed blood can also alter colour, so the vet considers appearance alongside the dog's history, gums, circulation and other signs. [14]

Watery diarrhoea can remove large amounts of fluid and salts from a dog's body, leading to dehydration, electrolyte imbalance and, in severe cases, shock.

The risk rises when losses are frequent or vomiting occurs as well. Puppies, older dogs and dogs with another illness may have less reserve, so their general condition deserves particular attention. [14]

Diarrhoea with profuse vomiting and severe abdominal pain can occur with an intestinal blockage and needs urgent veterinary assessment; collapse or breathing difficulty makes it an emergency.

A swallowed foreign object is one possible cause, but pancreatitis, severe gastroenteritis, toxins and other illnesses can look similar. Examination and imaging may be needed because symptoms alone cannot confirm a blockage. [12]

Puppies and older dogs can become dehydrated and weak more readily, so persistent or severe diarrhoea deserves prompt veterinary care even when the stool change began recently.

A puppy may also be more vulnerable to serious infection, while an older dog is more likely to have another condition or medicine that changes the risk. Age is considered with vaccination, appetite and general behaviour. [4]

A vet combines the dog's history with a physical examination, looking at hydration, circulation, temperature, abdominal comfort and any clues from diet, scavenging, medicines, travel or contact with other animals.

Faecal or blood tests and abdominal imaging are selected when the findings make infection, parasites, pancreatitis, a foreign object or another illness more likely. Not every dog needs every test. [14]

Usually not. ENOVAT recommends against antimicrobials for dogs with mild acute diarrhoea when they remain in good general condition without dehydration or systemic illness.

The veterinary assessment separates uncomplicated diarrhoea from severe disease or a specific infection where the balance may be different. Avoiding unnecessary antibiotics also helps protect the normal gut community and future antibiotic effectiveness. [15]

No. Blood in acute diarrhoea does not by itself show that a dog has a bacterial infection or will benefit from antibiotics.

ENOVAT recommends against antimicrobials even for mild haemorrhagic diarrhoea when a dog remains in good general condition without dehydration or systemic illness. Severity and the whole clinical picture guide the veterinary decision. [15]

Antibiotics are reserved for situations where their likely benefit outweighs their risks; uncomplicated acute diarrhoea often improves without them.

Unnecessary exposure can disturb helpful gut organisms and favours resistant bacteria, reducing how reliably important medicines work later. UK veterinary guidance therefore treats responsible prescribing as part of protecting animal and human health. [16]

Diarrhoea means a cat's stool is looser or more watery than normal, often with a change in frequency, volume or urgency.

Normal stool is usually formed and dark brown. A soft stool, repeated watery output, straining and small amounts containing mucus are different patterns, so litter-tray observations help describe what is happening. [17]

A sudden diet change, eating something unsuitable, worms, other parasites or pancreatitis can cause diarrhoea, while infection, toxins, a blockage and kidney, liver or inflammatory disease are other possibilities.

The stool's appearance does not identify one cause. Age, vaccination, appetite, vomiting, pain, recent food, hunting, medicines, travel and whether other cats are affected all help shape the veterinary assessment. [17]

An outdoor cat may visit the garden more often, have a dirty or sore-smelling bottom, clean around the tail excessively or develop low energy and an unkempt coat.

Gurgling, extra wind or a bloated abdomen can accompany diarrhoea, but none proves it alone. Changes in routine, appetite and grooming may be the first clues when the stool itself is not seen. [17]

Blood or mucus with vomiting, lethargy, abdominal pain or a cat that seems generally unwell needs prompt veterinary advice.

Fresh blood can come from irritation lower in the bowel, but appearance alone cannot identify the cause. The amount, repetition and cat's hydration and behaviour help determine how urgently assessment is needed. [17]

Black, tarry stool can be digested blood from bleeding in a cat's stomach or small intestine and warrants urgent veterinary advice.

It is different from a normally dark, formed stool. Food, medicines and swallowed blood can also affect colour, so the veterinary assessment considers the stool alongside the cat's gums, circulation, appetite and other signs. [18]

Kittens and older cats can become dehydrated more readily, so diarrhoea accompanied by weakness, vomiting, poor appetite or another sign deserves prompt veterinary care.

Watery stool removes fluid and salts, and a small or frail cat has less reserve when losses continue. Existing kidney, heart or other disease can further change how well the cat copes. [17]

Suspected poisoning or a swallowed object with diarrhoea is an emergency: contact a vet or emergency veterinary service immediately, particularly when vomiting, pain, weakness or collapse is also present.

Toxins and gut blockage are both recognised causes of feline diarrhoea. A partial obstruction can still allow some stool to pass, so diarrhoea does not rule out a dangerous blockage. [17]

A vet combines the cat's history with a physical examination, considering hydration, abdominal comfort, appetite, vomiting, diet, hunting, medicines, travel and contact with other cats.

Faecal or blood tests and abdominal imaging may follow when the findings suggest parasites, infection, pancreatitis, a foreign object or disease elsewhere in the body. The likely cause determines which tests add value. [18]

Usually not. Most acute diarrhoea is not caused by a disease-producing bacterial infection or settles without antimicrobials, so antibiotics are not a routine answer.

A vet may consider them when examination and testing support a specific bacterial problem or severe systemic illness. Unnecessary treatment can disrupt the normal gut community and contribute to antimicrobial resistance. [19]

Some organisms linked with diarrhoea can pass between animals and people, although a cat's diarrhoea is not automatically infectious or a risk to every person.

Campylobacter can live in the digestive tract of cats and dogs, and UKHSA lists contact with pets that have diarrhoea as one possible source of human infection. This makes careful hygiene around faeces and litter especially important. [20]