When an old dog is vomiting water and not eating, it can feel especially alarming. Senior dogs are more vulnerable to health issues, and symptoms like vomiting and appetite loss may signal more than just an upset stomach.
Whether your dog is simply having an off day or showing signs of a serious condition, understanding the reasons behind this behavior is essential.
We outline the most common causes, what you can do at home, and when it’s time to visit your vet.
Old Dog Vomiting Water and Not Eating: Why It Happens
An old dog vomiting water and not eating might be suffering from digestive upset, organ dysfunction, pancreatitis, toxin exposure, dental problems, or chronic illness.
Older dogs are less resilient, and symptoms like vomiting and loss of appetite can escalate quickly.
Sometimes they continue to drink water but vomit it up due to nausea or discomfort. It’s important to observe closely and act early.
Old Dog Vomiting Water and Not Eating: Common Causes
1. Age-Related Organ Dysfunction
As dogs age, their organs—especially the kidneys and liver—may begin to fail. These organs play key roles in filtering waste and supporting digestion.
If they’re not functioning properly, it can lead to nausea, vomiting water, and a decreased appetite.
You might also notice increased drinking, urination, or unusual behavior.
Chronic kidney or liver disease often develops gradually, but acute episodes can appear suddenly.
Related: Dog vomiting and not eating (Causes and when to worry)
2. Pancreatitis
Pancreatitis can strike dogs of any age, but it’s more common in older dogs—especially those fed rich or fatty foods.
This painful condition causes inflammation of the pancreas, leading to symptoms such as vomiting, abdominal pain, and refusal to eat.
Vomiting may occur even after drinking water. Your senior dog may appear restless, pant, or hunch over in pain. Pancreatitis can become dangerous without prompt care.
3. Gastrointestinal Irritation or Infection
Older dogs may have more sensitive digestive tracts.
They might vomit water and skip meals due to a bacterial infection, a sudden diet change, or something they ate outside.
Even mild irritation can cause nausea, which leads to vomiting and lack of interest in food.
Infections like gastroenteritis or parasites are also more taxing on aging bodies, so symptoms can hit harder and linger longer.
4. Dental Disease
One often overlooked cause of appetite loss in older dogs is dental pain.
If your dog is vomiting water and not eating, consider whether oral discomfort might be part of the problem.
Severe tartar buildup, broken teeth, infected gums, or oral tumors can make chewing painful—leading to skipped meals and eventual vomiting due to an empty or irritated stomach.
Dental issues are extremely common in senior dogs.
5. Cancer
Unfortunately, cancer becomes more common with age.
Tumors in the stomach, liver, or intestines may cause nausea, vomiting, and anorexia in older dogs.
Drinking may persist longer than eating, but eventually, vomiting water can occur as well.
Lethargy, weight loss, and pale gums are additional warning signs.
While not all cancers are terminal, any unexplained, persistent symptoms in an old dog warrant thorough veterinary evaluation.
Related: Old dog vomiting after drinking water and not eating (When to worry)
6. Toxin Exposure
Senior dogs may not be as curious as puppies, but they can still ingest something toxic—especially medications, plants, or even moldy food.
Vomiting, refusal to eat, and possible neurological symptoms could indicate poisoning.
If your old dog suddenly vomits water and won’t eat, especially after being in a garage, garden, or kitchen, consider toxin exposure as a potential cause.
7. Chronic Conditions Like Diabetes or Cushing’s Disease
Older dogs are more likely to suffer from chronic endocrine disorders. Diabetes and Cushing’s disease can both cause symptoms like vomiting, excessive thirst, and appetite changes.
If your dog has been drinking more water lately and then begins vomiting it, these conditions may be involved.
Diagnosis often requires blood tests, so don’t delay veterinary advice.
Related: Puppy throwing up water and not eating (Causes and what to do)
What to Do If Your Old Dog Is Vomiting Water and Not Eating
If your old dog is showing these symptoms but still seems alert, here are some steps you can take at home for the first 12–24 hours:
Withhold food for 12 hours to rest the stomach. However, do not withhold water unless vomiting continues immediately after drinking.
Offer ice chips or small sips of water to avoid dehydration.
Check hydration levels by gently lifting the skin between your dog’s shoulders. If it doesn’t snap back quickly, your dog may be dehydrated.
Reintroduce bland food after 12–24 hours. Use plain boiled chicken and white rice in small, soft portions that are easy to chew.
Keep your dog quiet and rested. Aging bodies take longer to recover, so stress and movement should be minimized.
Avoid over-the-counter medications without speaking to a vet. Many human meds are toxic to dogs, and older dogs metabolize drugs more slowly.
If symptoms don’t improve or worsen at any point, call your vet immediately.
When to Call or Visit Your Vet
You should seek veterinary attention promptly if:
Vomiting continues for more than 24 hours.
Your dog stops drinking or becomes lethargic.
Vomit contains blood or a foul odor.
Your dog has pre-existing conditions like kidney disease, diabetes, or heart problems.
You notice signs of pain, confusion, or collapse.
Your dog shows signs of dehydration or rapid weight loss.
Older dogs are more fragile, and they don’t bounce back as quickly.
Getting help early could make a major difference in outcome and comfort.
Related: Dog Vomiting Water and Not Eating but Drinking Water (Here’s why)
Key Takeaway
Seeing an old dog vomiting water and not eating is never easy.
As dogs age, their ability to cope with illness declines—and symptoms that might pass quickly in a younger dog can signal more serious issues in a senior.
Whether it’s pancreatitis, dental disease, or something more complex, these signs should never be ignored.
Monitor your dog closely, offer comfort, and act quickly if things don’t improve.
With the right care and timely intervention, many senior dogs bounce back and enjoy more good days with their families.