If your dog has diarrhea and is not eating but drinking water, it may raise both confusion and concern.
Many dog owners assume a dog that drinks water is relatively fine, but when the same dog refuses to eat and has loose stools, it can signal an issue worth exploring.
We explain why dog diarrhea and not eating but drinking water happens, what it could mean, and what steps you should take next.
Dog Diarrhea and Not Eating But Drinking Water: Why It Happens
Dog diarrhea and not eating but drinking water often occurs due to a range of underlying causes such as sudden dietary changes, gastrointestinal infections, food intolerance or allergies, stress or anxiety, ingestion of toxins, side effects of medication, and internal conditions like pancreatitis or liver disease.
These issues can upset your dog’s digestive system, leading to loose stools and a loss of appetite, while the body naturally maintains the urge to drink water to combat dehydration caused by diarrhea.
Dog Diarrhea and Not Eating But Drinking Water: Common Causes
Sudden dietary change
A sudden change in your dog’s food can easily lead to dog diarrhea and not eating but drinking water.
Dogs have sensitive digestive systems, and when their diet is abruptly altered—such as switching from wet food to dry kibble or introducing a new brand—it can cause stomach upset.
This dietary change may result in your dog refusing to eat due to nausea or stomach discomfort, while still drinking water to soothe their belly or counter fluid loss.
Some dogs may also avoid food entirely if it smells or tastes different than what they’re used to.
To prevent this, any change in a dog’s diet should be gradual, over 7–10 days, blending the new food with the old in increasing amounts.
Mild gastrointestinal infection
One of the most common causes of dog diarrhea and not eating but drinking water is a mild gastrointestinal infection.
Bacteria, viruses, or intestinal parasites can all upset a dog’s digestive tract.
While the infection might be mild enough that the dog stays alert and continues to drink water, it can still suppress appetite and cause diarrhea.
Infections like giardia or campylobacter can cause loose stools while the dog remains otherwise “normal” in behavior.
Drinking water helps replace the fluids lost through diarrhea, but the loss of appetite signals that the dog’s system is trying to fight something off.
A stool sample test at your vet’s office can help identify infections and guide treatment with antibiotics, antiparasitic medication, or probiotics.
Related: Dog diarrhea and not eating (Causes and when to worry)
Food intolerance or allergy
Food intolerance or allergic reactions to certain ingredients can also cause dog diarrhea and not eating but drinking water.
Common offenders include wheat, dairy, chicken, beef, and soy.
Dogs with sensitive stomachs may experience loose stools when exposed to such ingredients.
When experiencing discomfort, your dog may instinctively avoid eating, especially if the food source is what triggered the upset.
However, the urge to drink water remains, particularly if the diarrhea causes dehydration.
If you suspect a food-related cause, switching to a limited ingredient diet or hypoallergenic dog food under veterinary guidance can help.
Stress or anxiety
Dogs are creatures of routine, and disruptions in their environment can lead to stress-related symptoms such as diarrhea and appetite loss.
Common stress triggers include travel, moving homes, loud noises, or the introduction of a new pet.
When under stress, your dog may still drink water—either from true thirst or as a self-soothing behavior—but avoid food due to anxiety-related nausea or nervousness.
Behavioral changes such as pacing, whining, hiding, or restlessness may also accompany dog diarrhea and not eating but drinking water due to stress.
Try to create a calm, familiar environment and consider natural calming aids or consulting a vet about anxiety support.
Ingestion of toxins or spoiled food
Ingesting something toxic or spoiled can quickly result in dog diarrhea and not eating but drinking water.
Dogs are notorious for eating things they shouldn’t—leftovers from the trash, toxic plants, household cleaners, or human medications.
Vomiting and diarrhea are the body’s ways of trying to expel the toxins.
Affected dogs often refuse food due to nausea but drink water in an attempt to flush out their system.
If you suspect your dog has eaten something harmful, call your vet or poison control immediately.
Delaying treatment can lead to kidney or liver failure, seizures, or death in serious poisoning cases.
Side effects of medication
Certain medications, especially antibiotics, NSAIDs, or new prescriptions, can cause side effects such as dog diarrhea and not eating but drinking water.
The medication may upset your dog’s digestive tract, reduce appetite, or make them feel nauseous.
Some drugs, such as steroids or diuretics, may also cause increased thirst.
So if your dog recently started a new medication and now has diarrhea and a loss of appetite, but continues drinking water, the medication might be the cause.
Talk to your veterinarian about adjusting the dosage or switching medications if symptoms persist.
Related: Dog diarrhea and not eating or drinking (Here’s why)
Pancreatitis or other internal conditions
Pancreatitis, an inflammation of the pancreas, is another possible cause of dog diarrhea and not eating but drinking water.
Dogs with pancreatitis often present with a lack of appetite, diarrhea, and sometimes vomiting, but will still try to drink water due to dehydration.
Other internal conditions such as liver disease, kidney problems, or endocrine disorders like Addison’s disease or diabetes may also lead to similar symptoms.
A full veterinary workup, including bloodwork and imaging, is often needed to confirm these diagnoses.
What to do if your dog has diarrhea and is not eating but drinking water
If your dog is showing signs of diarrhea and not eating but drinking water, here are steps you can take:
Monitor closely for 24–48 hours
If your dog is otherwise active, alert, and showing no other symptoms (no vomiting, blood in stool, or signs of pain), monitor them for up to two days.
Offer small portions of bland food such as boiled chicken and white rice, and ensure they have access to fresh water.
Keep your dog hydrated
Even if your dog refuses food, it’s critical they continue drinking water.
Offer water regularly, and if needed, give ice chips or unflavored electrolyte solutions (dog-safe) to support hydration.
Do not force food
Avoid force-feeding your dog if they’re not interested in eating. Instead, try enticing them with bland, easy-to-digest meals.
Forcing food may increase stress or trigger vomiting.
Withhold treats or rich foods
Do not offer fatty or rich treats while your dog has diarrhea.
This can worsen the gastrointestinal upset and delay recovery.
When to see the vet immediately
You should contact your veterinarian if any of the following occur:
Diarrhea lasts longer than 48 hours
There is blood or mucus in the stool
Vomiting occurs along with diarrhea
Your dog becomes lethargic or unresponsive
Signs of dehydration such as sunken eyes, dry gums, or poor skin elasticity
Your dog is a puppy, senior, or has a pre-existing condition
You suspect your dog ingested something toxic
Veterinarians may perform tests such as fecal analysis, blood panels, or x-rays to identify the cause and recommend treatment including fluids, medication, or dietary changes.
Key Takeaway
Dog diarrhea and not eating but drinking water is not uncommon, but it should never be ignored—especially if the symptoms persist for more than a day.
While occasional stomach upset may pass on its own, consistent refusal to eat combined with diarrhea signals that something deeper may be going on.
The fact that your dog is still drinking water is reassuring, as it shows they are attempting to stay hydrated.
However, hydration alone doesn’t mean they are recovering, especially if their appetite doesn’t return or other symptoms develop.
In most cases, addressing the root cause of dog diarrhea and not eating but drinking water requires a thorough evaluation by a veterinarian.
Prompt action can prevent complications and help your dog recover faster.
Always trust your instincts—if something feels off with your dog, it’s better to be safe and get expert advice.
By staying observant and proactive, you’re giving your furry friend the best chance to bounce back healthy and happy.