When an old dog is throwing up and not eating, it’s never something to take lightly.
Senior dogs are more vulnerable to health issues, and symptoms like vomiting combined with appetite loss often indicate a deeper, possibly serious condition.
While some causes may be mild, others can signal systemic disease, organ dysfunction, or even cancer.
We outline what causes these symptoms, what you can do at home to stabilize your dog, and when to seek veterinary help without delay.
Old Dog Throwing Up and Not Eating: Why It Happens
An old dog throwing up and not eating could be experiencing chronic illness, gastrointestinal disease, pancreatitis, cancer, kidney or liver failure, or a reaction to medications. Vomiting and loss of appetite are commonly linked to discomfort, nausea, or systemic stress in senior dogs.
Since aging dogs have weaker immunity and organ function, even mild symptoms can lead to rapid decline without timely care.
Old Dog Throwing Up and Not Eating: Common Causes
1. Kidney or Liver Disease
Age-related kidney or liver dysfunction is one of the most common reasons older dogs throw up and avoid food.
As toxins build up in the bloodstream, dogs experience nausea, vomiting, and a complete loss of appetite.
Signs like weight loss, increased urination, bad breath, or yellowing gums may also be present.
Bloodwork and urine tests can help confirm organ decline and determine next steps.
2. Pancreatitis
Inflammation of the pancreas can occur suddenly, even in dogs who have never had digestive issues.
Senior dogs are especially at risk after eating a fatty meal or if they’re on certain medications.
Pancreatitis causes vomiting, abdominal pain, weakness, and food refusal. Dogs may adopt a “praying position” (front legs down, rear up) to ease the discomfort.
It often requires fluid therapy, anti-nausea meds, and supportive care.
Related: Dog vomiting and not eating (Causes and when to worry)
3. Cancer
Unfortunately, cancer becomes more common as dogs age. Tumors in the digestive tract, liver, or pancreas can cause vomiting and suppress appetite.
Other types of cancer may cause general systemic weakness and nausea due to pain or internal changes.
If your senior dog is throwing up frequently and losing weight or interest in daily activities, your vet may recommend imaging or biopsies.
4. Side Effects of Medication
Many older dogs take medications for arthritis, heart disease, or thyroid issues.
Some of these, particularly non-steroidal anti-inflammatory drugs (NSAIDs), can irritate the stomach lining or interact with other medications.
If your dog recently started a new medication and began vomiting and avoiding food soon after, speak with your vet about possible side effects or the need for a dosage adjustment.
5. Cognitive Dysfunction or Stress
Cognitive decline—similar to dementia in humans—can cause changes in eating patterns, stress response, and nausea.
A dog with canine cognitive dysfunction may forget to eat, become disoriented, or react abnormally to daily routines.
Vomiting may follow prolonged fasting or anxiety-related stomach upset.
Watch for other signs like pacing, confusion, whining, or staring at walls.
6. Dental Pain or Oral Tumors
Dental disease is incredibly common in senior dogs and often goes unnoticed.
Rotten teeth, gum infections, or oral growths can make eating painful, leading to food refusal.
Vomiting may follow attempts to eat or may occur from nausea related to poor dental health.
If your dog avoids hard food or flinches when touched around the mouth, a dental exam is warranted.
7. Gastrointestinal Obstruction
Older dogs can still swallow things they shouldn’t—or develop blockages due to tumors, scar tissue, or chronic inflammation.
If vomiting is persistent and your dog refuses all food and water, seems bloated, or strains without producing stool, an obstruction is likely.
This is a surgical emergency that should be addressed immediately.
What to Do If Your Old Dog Is Throwing Up and Not Eating
If your senior dog has just started showing these symptoms, and seems alert and stable, you can try short-term care at home:
Withhold food for 12 hours, but continue to offer water or ice cubes in small amounts.
Start a bland diet like boiled chicken and white rice after the rest period—offered in tiny, soft portions.
Elevate food and water bowls to reduce strain and make eating more comfortable for arthritic dogs.
Use slow-feeder bowls or puzzle feeders if your dog tends to eat too quickly.
Limit stress and keep your dog in a calm, familiar environment.
However, do not wait more than 24 hours if your dog refuses food, continues vomiting, or shows signs of dehydration, weakness, or pain.
When to Call or Visit Your Vet
Contact your veterinarian right away if:
Your old dog has vomited multiple times in 24 hours.
Appetite is completely gone and water is also refused.
There are signs of dehydration (dry gums, sunken eyes, reduced urination).
Vomit contains blood or is accompanied by diarrhea.
Your dog appears bloated, shaky, lethargic, or confused.
You notice yellow gums, labored breathing, or sudden weight loss.
Your dog is already managing chronic illness or taking medications.
Senior dogs are at a higher risk of complications from dehydration, organ stress, or digestive upset.
Early intervention may prevent hospitalization or more severe outcomes.
Related: Old Dog Vomiting Water and Not Eating (Here’s why)
Read more: Dog Vomiting Yellow and Not Eating or Drinking (When to worry)
Key Takeaway
An old dog throwing up and not eating may be facing more than just a minor stomach upset.
Vomiting and loss of appetite can signal significant issues like organ failure, pancreatitis, cancer, or serious discomfort.
Because senior dogs decline faster and have reduced physical reserves, time is of the essence.
Monitor your dog closely, keep them hydrated, and reach out to your vet quickly if symptoms continue or worsen.
Your vigilance, patience, and prompt action can make a real difference in helping your senior dog feel better and stay comfortable.