Cat Diarrhea: Causes, Treatment, and When to See a Vet
Most cat diarrhea is mild and passes within a day or two, but some cases signal parasites, infection, or chronic disease. A vet explains the common causes, what stool changes mean, safe home care, what to feed, and exactly when to call your vet.
MRCVS BVMS, BS ASci, MLitt
Medically reviewed by Dr. Caitlin Merrill, MRCVS BVMS, BS ASci, MLitt · Last reviewed
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Cat diarrhea is loose, watery, or unformed stool that passes more often than normal.
Most episodes in a healthy adult cat are short-lived and settle within a day or two, often after a diet change or a stressful event, according to the Cornell Feline Health Center. Some cases signal parasites, infection, or a chronic disease that needs a vet.
This vet-written guide explains why your cat has diarrhea, how to read what you find in the litter box, what you can safely do at home, what to feed, and exactly when cat diarrhea stops being a wait-and-see problem.
- 1One or two soft stools in a bright, eating, drinking adult cat can be watched at home for 24 to 48 hours.
- 2Diet changes, stress, parasites, and infections are the most common causes; diarrhea lasting three weeks or more points to a chronic condition.
- 3Keep water available, feed small bland or veterinary GI meals, and never give human anti-diarrhea medicines to a cat.
- 4Blood, black or tarry stool, repeated vomiting, lethargy, or refusing food means call your vet the same day.
- 5Kittens and senior cats dehydrate fast and should see a vet sooner, not later.
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Cat diarrhea at a glance: watch, call, or go now
The first decision is not "what caused this" but "how urgent is this." Use the table below to place your cat, then read the sections that match. It combines the duration, the cat's age, and the warning signs that veterinary sources treat as the tipping points.
| Your cat right now | What to do | How long to wait |
|---|---|---|
| Adult cat, one or two soft or loose stools, eating and drinking, acting normal | Home care: water, small bland meals, clean litter box | Reassess at 24 hours; call the vet if it continues at 48 hours |
| Diarrhea with vomiting, or diarrhea that is very watery | Call your vet today; a cat loses fluid fast when both happen | Same day |
| Fresh red blood, mucus, or yellow or green diarrhea | Call your vet today and bring a stool sample | Same day |
| Black, tarry stool, pale gums, weakness, collapse, or a kitten who is limp | Emergency clinic now | Do not wait |
| Kitten, senior cat, or a cat with diabetes, kidney disease, or hyperthyroidism | Call your vet the day it starts | Same day |
| Soft stool that comes and goes for more than two to three weeks | Book a non-urgent appointment and start a stool diary | Within the week |
Quick urgency triage comes down to duration, age, and red flags: how long it has lasted, how young or old your cat is, and whether any warning sign in the table is present.
VCA Animal Hospitals advises consulting your veterinarian when frequent liquid or semi-liquid stools persist for more than two days, and sooner when the diarrhea is severe or bloody or your cat shows generalized signs of illness such as weakness, fever, vomiting, or appetite loss (VCA).
My cat has diarrhea but is acting normal: should I worry?
A cat with diarrhea who is still eating, playing, and using the litter box is usually not an emergency.
A bright, well-hydrated adult with one or two soft stools can be monitored at home for 24 to 48 hours while you look for an obvious trigger. Common ones include:
- A new treat, table scrap, or a sudden food switch
- A houseguest, a new pet, or a change in routine
- A trip in the carrier or a stay at the clinic
- A recent dose of antibiotics or a dewormer
A cat that seems fine, is acting fine, and still has a good appetite is the best-case version of cat diarrhea. Acting normal still does not guarantee everything is fine.
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Cats hide illness well, and every loose stool costs fluid and electrolytes. The Merck Veterinary Manual notes that continuing diarrhea matters because dehydration and electrolyte imbalance, which can progress to shock, follow large fluid losses (Merck Veterinary Manual).
While you watch, keep fresh water within easy reach in more than one spot. Many cats drink more from moving water, and a quiet fountain makes it easier to notice whether your cat is actually drinking.
Will cat diarrhea resolve on its own? Often, yes, when the trigger was a treat or a stressful day.
Cornell notes that an abrupt diet change may cause a few days of diarrhea, and a stressful event such as a car trip or a clinic stay can produce a brief episode. Diarrhea that is watery, repeated, or still present at 48 hours usually has a cause that needs treating.
So when should you worry? A call to the vet replaces watching when:
- The diarrhea passes 48 hours
- It turns watery or bloody
- Your cat stops eating, hides, or vomits
Older cats deserve extra caution here, because hyperthyroidism and kidney disease often show up first as digestive changes. Our guide to senior cat digestive problems covers the age-specific signs to watch.
What is the best anti-diarrhea medicine for cats without a vet? There is no safe over-the-counter option. VCA advises extreme caution with loperamide (Imodium) in cats, if it is used at all, so stick to water and small bland meals and let your vet choose any medicine (VCA).
Why your cat has diarrhea: the most common causes
Diarrhea is a symptom, not a disease. What gives a cat diarrhea ranges from harmless to serious, and the reasons differ between an indoor house cat and an outdoor hunter, between a kitten and a senior, and between one sudden episode and months of soft stool.
The usual culprits:
- Diet: a sudden change, a new treat, or something scavenged
- Stress: a move, a guest, a trip, a new pet
- Parasites: worms, Giardia, coccidia
- Infection: bacterial or viral, including panleukopenia
- Conditions outside the gut when it drags on: an overactive thyroid, kidney or liver disease, or lymphoma
These are the broad buckets.
Why does a cat get diarrhea from these? Each one either speeds the gut up, irritates its lining, or stops it absorbing water, and the stool turns loose.
The most common causes are covered below in the order vets usually consider them, starting with the ones you can often fix at home and ending with the diseases that need a workup.
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Sudden diet changes and eating something they should not
Cats' digestive systems do not handle change well. Switching brands or protein sources overnight is one of the most common reasons an otherwise healthy cat has diarrhea. So is raiding the garbage, sampling a houseplant, or being given rich human food.
Mild cases from a dietary slip usually settle in a day or two once the cat is back on a stable diet. If the "something" might have been a toxic plant or a chemical, call your vet or a poison line first; our list of plants toxic to cats covers the common household offenders.
Food intolerance and sensitivities
Some cats react to a specific ingredient rather than to change itself. Chicken, beef, fish, and dairy are frequent triggers. You may see recurring soft stool, gas, or vomiting rather than one dramatic episode. VCA lists food intolerance and food allergy among the causes vets consider when diarrhea keeps returning.
The fix is a diet trial under your vet's direction, usually a veterinary gastrointestinal diet or a novel or hydrolyzed protein for several weeks.
Merck notes vets may recommend a protein your cat has never eaten, such as lamb, venison, or rabbit, to identify a food allergy. If your cat has already been diagnosed, see what to feed a cat with IBD.
Parasites: worms, Giardia, coccidia
Kittens, outdoor cats, and new rescues are at the highest risk. Cornell reports that roundworms affect 25 to 75 percent of cats, with higher rates in kittens, and that virtually all cats pick up coccidia (Isospora) at some point in life (Cornell Feline Health Center).
Giardia is less common, found in under 5 percent of cats, but rates climb in multi-cat homes and breeding facilities.
Signs that point toward parasites include:
- Soft stool with mucus or occasional streaks of blood
- A pot-bellied look or poor growth in kittens
- Weight loss despite a normal appetite
- Visible worms or rice-like segments in the stool
A routine fecal flotation can miss Giardia, so your vet may run a specific antigen test (VCA).
Our guides to worms in cats, coccidia in cats, and what worms look like in cat poop explain what to bring to the appointment.
Infections: bacterial and viral
Salmonella, Campylobacter, and Clostridium can cause diarrhea, especially in cats fed raw diets or living in crowded conditions. The viral cause every owner should know is feline panleukopenia.
Merck describes it as highly contagious and often fatal, with kittens hit hardest, and notes that vomiting typically starts a day or two after the fever and extreme dehydration can develop rapidly (Merck Veterinary Manual).
Vaccination is the reason panleukopenia is now uncommon in pet cats. An unvaccinated kitten with diarrhea and lethargy is an emergency; read panleukopenia in cats and check your kitten's status against our kitten vaccine schedule.
Stress
Stress changes gut motility and the gut's bacterial balance. A move, renovations, a new pet, boarding, or even a rearranged room can rattle a sensitive cat.
Cornell cites a long car trip or a weekend at the clinic as classic triggers of a brief episode. Stress diarrhea usually clears within a day or two of the routine settling, and probiotics are often suggested for stressful events (VCA).
Antibiotics and other medications
Can antibiotics give cats diarrhea? Yes. Antibiotics disturb the normal gut bacteria, and VCA lists antibiotic use as one of the common reasons vets recommend a probiotic. Other drugs, including some pain relievers and dewormers, can loosen stool too.
A cat on antibiotics for diarrhea can also get worse before it gets better if the drug was not the right fit, which is one reason vets prefer a fecal test before reaching for an antibiotic.
Antibiotic diarrhea usually settles within a few days of the course ending; if it does not, or if your cat stops eating during treatment, call the clinic.
Chronic disease: IBD, hyperthyroidism, kidney disease, cancer
When diarrhea persists for weeks or keeps coming back, vets look beyond the gut. Cornell's IBD overview lists vomiting, weight loss, diarrhea, bloody stools, lethargy, and decreased appetite as the typical signs, most often in middle-aged and older cats (Cornell Feline Health Center).
Hyperthyroidism, a common disease of middle-aged and older cats, speeds everything up including the gut (Cornell). Kidney and liver disease, pancreatitis, and intestinal lymphoma are the other usual suspects; Merck notes lymphoma and adenocarcinoma are the common intestinal tumors in cats. See hyperthyroidism in cats and kidney disease in cats for the signs that overlap.
Many of these triggers affect dogs too. In a multi-pet home, our companion guide to why your dog has diarrhea covers the canine side.
Acute or chronic: why the timeline changes the plan
Acute diarrhea starts suddenly and lasts from a day to under two weeks. It is usually dietary, stress-related, or infectious, and most cases respond to conservative care without the cause ever being pinned down, as VCA notes.
Chronic diarrhea is different. Merck's professional manual defines chronic enteropathy as GI signs such as diarrhea, vomiting, or appetite loss lasting three weeks or longer (Merck Veterinary Manual). At that point the likely causes shift toward food sensitivity, parasites that were missed, IBD, hyperthyroidism, or cancer, and the workup gets more thorough.
A useful way to describe it to your vet:
- Did it start all of a sudden, or build gradually?
- Has it gone on for three days, a week, or longer?
- Does your cat keep having it on and off, or have it all the time?
Those three answers shape the workup.
A persistent pattern over weeks is chronic even if each bout seems mild.
If your cat swings the other way and strains to pass hard, dry stool, read our guide to constipation in cats. Liquid stool can leak around a hard fecal mass and be mistaken for diarrhea.
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What your cat's poop is telling you
What does cat diarrhea look like, and does it matter? Color and texture offer genuine clues, from soft stool that is not quite diarrhea to watery or yellow diarrhea.
None replaces a vet exam, but they help you judge urgency and give your veterinarian a head start. Scoop daily while your cat is unwell so you can report changes accurately.
| What you see | What it can mean | Urgency level |
|---|---|---|
| Soft but formed stool | Mild upset from a diet change or stress | Low: monitor at home for 24 to 48 hours |
| Watery diarrhea | Rapid transit through the gut; higher dehydration risk | Moderate: call the vet if it lasts beyond 24 to 48 hours |
| Red streaks or fresh blood | Irritation or inflammation in the colon or rectum, sometimes parasites | High: call your vet the same day |
| Black or tarry stool | Digested blood from bleeding higher in the digestive tract | Emergency: see a vet immediately |
| Yellow or green stool | Food moving through too fast, bile changes, occasionally liver or gallbladder disease | Moderate: vet visit if it persists or repeats |
| Mucus or a jelly-like coating | Inflammation of the colon (colitis), often stress or parasite related | Moderate: vet visit if ongoing |
| Greasy, pale, or gray stool | Poor digestion or absorption, sometimes pancreatic disease | High: book a vet visit promptly |
| Visible worms or rice-like segments | Roundworms or tapeworms | Moderate: vet for deworming, bring a stool sample |
What does cat diarrhea with blood mean? In bloody diarrhea the color is the clue. Bright red blood usually comes from the colon or rectum (colitis, parasites, stress) and means a same-day vet call. Black, tarry stool can signal bleeding in the stomach or small intestine and needs a vet now (Merck Veterinary Manual).
Three findings deserve a closer look on their own pages: blood in cat poop, black cat poop, and mucus in cat poop.
A stool diary makes these patterns easier to spot. Keep a note on your phone or taped near the litter box, and log the date, consistency, and color of each stool, plus any food, treat, or litter change. A few days of entries turn vague impressions into a clear record you can share.
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Cat diarrhea and vomiting together
A cat that is vomiting and has diarrhea at the same time is losing fluid from both ends, and the list of causes narrows:
- Gastroenteritis from a dietary slip or infection
- A toxin, including plants and human medicines
- A swallowed object such as string or a hair tie
- Pancreatitis
- Panleukopenia in an unvaccinated cat or kitten
Cornell advises that cats who vomit and have simultaneous diarrhea should be evaluated by a veterinarian promptly (Cornell Feline Health Center).
Is cat diarrhea and vomiting an emergency? Treat it as a same-day vet call, and go sooner if the vomit or diarrhea keeps coming, your cat cannot keep water down, there is blood, or the cat is weak, lethargic, a kitten, or a senior. Hold off on home bland-diet care until your vet weighs in.
Our dedicated guide to a cat throwing up and diarrhea walks through the combined picture, and gastroenteritis in cats explains the most common diagnosis behind it.
When to see the vet for cat diarrhea
Call your veterinarian if any of the following apply:
- Diarrhea lasts more than 24 to 48 hours
- Stool contains blood or mucus, or is black and tarry
- Your cat is vomiting as well, or refusing food or water
- Hiding, lethargy, weakness, or signs of dehydration
- Weight loss, or a change in thirst or urination
- Your cat is a kitten, a senior, or has a chronic illness such as diabetes or kidney disease
- You know or suspect your cat ate something toxic, even before diarrhea starts
Watery diarrhea, vomiting, and refusing to eat and drink can lead to dehydration within a day. Call immediately if these appear together. Cat diarrhea with blood always earns a same-day call, and black, tarry stool means go now.
Cat diarrhea with mucus, a clear or jelly-like coating on the stool, usually means the colon is inflamed.
On its own it is a call-today sign rather than an emergency, but mucus plus fresh red blood, vomiting, or lethargy is a red flag that moves it up the list. Our guide to mucus in cat poop explains what the coating means and how vets treat colitis.
Kittens and senior cats dehydrate fast
Kittens, elderly cats, and cats with chronic disease have far less reserve than healthy adults. A kitten with watery diarrhea can become dangerously dehydrated in hours, and Merck notes that kittens under five months are the most likely to die from panleukopenia.
Senior cats often have reduced kidney function, so fluid loss hits harder. For these cats, call the day the diarrhea starts.
Cat diarrhea treatment at home: what is safe
Can you help a cat with diarrhea without a trip to the vet? For a single mild bout in a healthy adult, yes. The goal of home treatment for cat diarrhea is simple: keep fluids up, rest the gut without starving it, and watch closely. If nothing has improved by 48 hours, it is time to call.
Home remedies for cat diarrhea support the gut while it recovers; they do not treat parasites, infections, or disease. There is no natural cure for cat diarrhea, because the cure is treating whatever caused it.
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Yogurt is a common suggestion, but most cats digest dairy poorly and it is not a reliable probiotic source. In short:
- Give: fresh water, small bland or GI-diet meals, a cat probiotic, a little plain pumpkin
- Do not give: human medicines, dairy, or a fast for a kitten, senior, or thin cat
Should you fast a cat with diarrhea?
Cats are not small dogs here. VCA says a vet may advise withholding food for a short time in an otherwise healthy adult, and Merck notes a 24 to 48 hour food rest is sometimes used for colitis, but both frame it as a vet's call.
Cats that stop eating are at risk of hepatic lipidosis, a fatty-liver condition that Cornell links to a period of near-total appetite loss (Cornell Feline Health Center).
The safer default for most cats is to skip the fast and move straight to small, frequent bland meals. Never fast a kitten, a senior, an underweight cat, or an overweight cat without your vet's direction, and never withhold water.
Keep your cat hydrated
Offer fresh water in several places, away from the food bowl, and consider a pet water fountain if your cat prefers running water.
Switching to or adding wet food raises water intake with every meal. Cat-specific electrolyte supplements can help a reluctant drinker, but a cat that will not drink at all needs a vet, not a supplement.
Keep the litter box clean and easy to reach. Frequent scooping also lets you track whether the stool is firming up day by day.
Consider a cat-specific probiotic
Probiotics are live beneficial bacteria that help restore the gut's normal balance after it has been disrupted by diet changes, medications, or stress. VCA lists them as commonly used for diarrhea linked to inflammatory bowel disease, antibiotic use, or stressful events, and names feline products such as FortiFlora and Proviable (VCA).
Choose a product made for cats, since human and dog strains and doses differ, and ask your vet which one they trust; VCA notes the FDA does not review supplements for effectiveness before sale. Our guide to cat probiotics compares the main types.
Give the probiotic once daily with food for at least a week, or for the length of any antibiotic course plus a few days after. Probiotics for cat diarrhea are a support, not a treatment: if the stool has not improved in two or three days, the probiotic is not the missing piece.
Cat diarrhea medicine: what never to give
There is no safe over-the-counter diarrhea medicine for cats to reach for without a vet. Cornell warns that some over-the-counter medications can be harmful to cats, and the two most owners have at home are the worst offenders.
Cat diarrhea medication that is safe exists, but it is prescription only: dewormers, anti-protozoals such as metronidazole or fenbendazole, anti-nausea drugs, and in some cases a short course of a feline-appropriate anti-diarrheal chosen by your vet after an exam.
Sources for the warning above:
What to feed a cat with diarrhea
What should you feed a cat with diarrhea? Something bland, highly digestible, and fed in small portions several times a day. The gut heals faster when it is working gently than when it is empty, and small meals are less likely to come straight back up.
The best cat food for diarrhea is not a brand but a type: a highly digestible bland diet or a veterinary GI diet for the first few days, then a sensitive-stomach or regular complete diet once stool is formed.
Homemade food has a place for 48 to 72 hours, canned or wet food helps with hydration, and the rules below cover each, including how to move back to the normal diet without restarting the problem.
Start with a bland or veterinary GI diet
Two options work well:
- A home bland diet: plain boiled, unseasoned chicken breast or white fish, with or without a little plain white rice, for two to three days
- A veterinary gastrointestinal diet your vet authorizes, which is complete and balanced and can be fed for as long as needed
For the home bland diet, keep the protein portion generous because cats are obligate carnivores, and feed small portions every three to four hours for two to three days. Our guide to whether cats can eat rice covers the limits on the rice portion.
For the veterinary option, a gastrointestinal diet such as Hill's Prescription Diet i/d is what most clinics reach for, and your vet can authorize it. VCA describes what these diets offer:
- A balance of fibers that feed the good bacteria in the gut
- Antioxidants that support the immune system
- Complete and balanced nutrition, which a chicken-and-rice plate is not
For anything longer than a few days, the veterinary diet is the better choice.
Add plain canned pumpkin for fiber
A teaspoon of plain canned pumpkin mixed into meals adds soluble fiber that can help firm loose stool. Merck notes that soluble fiber is often added to the diet once feeding resumes after a bout of colitis.
Use pure pumpkin, not pie filling, which contains sugar and spices, and start small: too much fiber can loosen stool again. A fiber powder made for pets is an alternative if your cat refuses pumpkin.
Pumpkin for cat diarrhea works best on soft, colitis-type stool and does little for watery diarrhea from infection or parasites. Give it for three to five days alongside the bland or GI diet, then stop once stool is formed; long-term fiber is a decision for your vet, not a daily habit.
Does wet food cause diarrhea in cats?
Wet food itself is not a cause of diarrhea, and its moisture content, at least 75 percent according to Cornell's feeding guidance, helps a cat with loose stool stay hydrated (Cornell Feline Health Center).
What causes trouble is a sudden switch from dry to wet, a new flavor or brand, or a rich, high-fat recipe. If you want to move to wet food, do it gradually, and if a specific can reliably produces soft stool, that recipe is the problem, not wet food as a category.
Moving back to the normal diet
Once stools have been formed for two to three days, transition back to the regular food over seven to ten days, mixing a little more of the normal food in each day, as VCA recommends.
Rushing this step is the most common reason diarrhea comes straight back. If the regular food itself seems to be the trigger, ask your vet about a long-term sensitive-stomach or GI diet rather than cycling through brands.
How vets diagnose the cause of cat diarrhea
Your vet visit starts with a history and a top-to-tail exam that checks for pain, dehydration, body condition, and abdominal masses. Bring a fresh stool sample collected the same day; VCA notes the color, consistency, smell, and frequency all help narrow the cause.
From there the workup is stepwise:
- Fecal tests for worms, Giardia, coccidia, and sometimes bacterial culture or PCR
- Bloodwork for thyroid, kidney, and liver function, plus folate and B12 levels, which Cornell notes can drop when the gut is inflamed
- Imaging (X-rays or ultrasound) to look for blockages, thickened bowel, enlarged lymph nodes, or tumors
- A diet trial of several weeks to confirm a food sensitivity
- Endoscopy or biopsy when IBD or intestinal lymphoma is suspected, because the two can be hard to tell apart
For a mild case your vet may skip most of this and treat conservatively first; VCA notes further testing is usually reserved for cats that do not improve within two days or that get worse.
Vet treatment options for cat diarrhea
Treatment follows the diagnosis. Depending on the cause, your veterinarian may prescribe:
- Dewormers or anti-protozoal drugs for parasites; VCA notes Giardia is usually treated with fenbendazole or metronidazole for five to seven days (see our guides to fenbendazole for cats and cat dewormer)
- Fluids under the skin or into a vein, anti-nausea medication, and a bland diet for infectious or severe cases
- A hypoallergenic, novel-protein, or hydrolyzed diet for food sensitivities
- Diet change, probiotics, metronidazole, or corticosteroids for IBD; Cornell notes most cats with IBD need some form of long-term management
- Treatment of the underlying disease when the gut is not the real problem, such as medication for hyperthyroidism
- Pheromone diffusers, enrichment, and routine changes for stress-driven diarrhea
Never repurpose leftover medications or share drugs between pets. Doses that are safe for a dog or a person can be dangerous for a cat.
Kitten diarrhea and senior cat diarrhea
Kitten diarrhea is common during weaning as the gut adjusts to solid food, and Cornell notes kittens are at elevated risk for that reason. It is also the age group most likely to carry roundworms and coccidia, and the age most vulnerable to panleukopenia.
The rule for kittens is tighter than for adults: a kitten with watery diarrhea, or any diarrhea plus lethargy or not eating, needs a vet the same day.
Kitten home remedies are limited to:
- Small, frequent meals of kitten food or plain boiled chicken
- Syringe-fed water or kitten milk replacer if the kitten is not drinking
- A kitten-safe probiotic your vet approves
Never fast a kitten. Our guides to weaning kittens and how to tell if a kitten has worms cover the two most common kitten triggers.
Senior cat diarrhea deserves the same low threshold for a different reason. In an older or elderly cat, new or recurring loose stool is more likely to be the first sign of hyperthyroidism, kidney disease, IBD, or intestinal lymphoma than of a dietary slip.
What if an older cat has diarrhea but seems fine? Call your vet the day it starts anyway. Seniors have less fluid reserve and often reduced kidney function, and early hyperthyroidism or kidney disease can look like a cat who is eating and acting normal apart from the litter box.
At the visit, mention weight loss, increased thirst, or a change in appetite. If vomiting is part of the picture, old cat throwing up covers the senior-specific causes.
Preventing diarrhea in cats
Once your cat is on the mend, a few habits lower the odds of a repeat:
- Transition any new food slowly over 7 to 10 days rather than all at once
- Introduce new treats one at a time, in small amounts
- Feed a consistent, complete, and balanced diet; cats that do well on one food rarely need variety
- Keep toxic plants, chemicals, and rich table scraps out of reach
- Plan ahead for travel, boarding, and household changes to limit stress
- Keep year-round parasite prevention and annual fecal checks current, and keep vaccinations up to date
- Scoop daily, so you catch a change in stool early rather than days later
Most cases of feline diarrhea are temporary and resolve with the right supportive care. Hydration, close monitoring, and an early vet visit for anything persistent, bloody, or paired with vomiting give your cat the best chance of a quick, uncomplicated recovery.
Cat diarrhea FAQs
Frequently Asked Questions
What stops diarrhea fast in cats?
Nothing safe works in hours, and the fastest route is removing the trigger. For a mild case, go back to the cat's usual food (or a bland meal), add a little plain pumpkin for fiber, keep water available, and give a cat probiotic. Most dietary or stress episodes firm up within one to two days. Anything that promises to stop diarrhea instantly, including human medicines, is unsafe for cats.
Can stress cause diarrhea in cats?
Yes. Stress changes gut motility and the balance of gut bacteria, and Cornell lists stressful events such as a long car trip or a clinic stay as common triggers of a brief episode. Stress diarrhea usually clears within a day or two once the routine settles. If it does not, or if it recurs with every change, ask your vet about probiotics, pheromone diffusers, and ruling out an underlying condition.
My cat has had diarrhea for a week. Is that an emergency?
A week of diarrhea is not usually an emergency if your cat is eating, drinking, and alert, but it is well past the point for home care. Book a vet visit now and bring a stool sample. Diarrhea that persists for three weeks or more meets the definition of a chronic enteropathy, and the causes at that stage, including parasites, food sensitivity, IBD, and hyperthyroidism, need testing to find.
Is cat diarrhea contagious to other cats or people?
It depends on the cause. Dietary and stress diarrhea is not contagious. Parasites such as Giardia and roundworms, and viruses such as panleukopenia, can spread between cats through shared litter boxes, and VCA notes Giardia can also affect people, so wash your hands and disinfect boxes while a cat is being treated. Keep an unwell cat's litter box separate until your vet has ruled out an infectious cause.
Can I give my kitten the same home remedies as an adult cat?
Only the gentle ones. Small frequent meals, fresh water, and a vet-approved probiotic are fine for kittens. Fasting is not: kittens have tiny reserves and dehydrate in hours. Pumpkin should be a very small amount, and no over-the-counter medicine of any kind should be given. If a kitten has watery diarrhea or is also lethargic or off food, call your vet the same day.
What could be causing my cat's upset stomach?
The same triggers behind diarrhea cause most upset stomachs in cats: a diet change, eating something unusual, stress, parasites, or hairballs. If vomiting is the main sign, with or without diarrhea, our guide to a cat throwing up sorts the causes by what the vomit looks like and how often it happens.
Author Bio
Caitlin Merrill MRCVS, BVMS, BS ASci, MLitt
Caitlin is a primary care clinician based at the University of Glasgow. She currently splits her time between clinical work, teaching, and writing. When not working she can be found hiking the moors with her mildly dramatic terrier or cuddling on the sofa with her wildly naughty cat.
Feature image: istockphoto
Veterinarian · MRCVS BVMS, BS ASci, MLitt
Caitlin is a primary care clinician based at the University of Glasgow. She currently splits her time between clinical work, teaching, and writing. When not working she can be found hiking the moors with her mildly dramatic terrier or cuddling on the sofa with her wildly naughty cat.
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Gastroenteritis in Cats: Symptoms, Causes, Treatment, and When to See a Vet
