When your dog is sick and suddenly stops eating or drinking, it’s more than just worrisome — it’s a potential emergency. Appetite and hydration are critical indicators of your dog’s overall health.
We outline the common causes of a dog being sick and not eating or drinking, what you can do at home, and when to seek veterinary help.
Dog Sick and Not Eating or Drinking — Why It Happens
Dogs that are unwell often experience nausea, pain, or fatigue that suppress their appetite and drive to drink. Common causes include gastrointestinal infections, pancreatitis, kidney disease, toxin exposure, or even something as simple as motion sickness.
Some of these issues can pass with rest, while others may require urgent medical intervention to prevent dehydration or organ damage.
Common Causes of Dog Sick and Not Eating or Drinking
Gastroenteritis
Gastroenteritis is inflammation of the stomach and intestines, usually caused by bacteria, viruses, or something your dog ingested.
A dog with gastroenteritis will often vomit, have diarrhea, and show disinterest in food and water due to nausea.
This condition can range from mild to severe. In serious cases, it can lead to dehydration and electrolyte imbalances if fluids aren’t replaced.
Pancreatitis
Pancreatitis occurs when the pancreas becomes inflamed, often after eating rich or fatty foods.
It causes abdominal pain, vomiting, and lethargy. Dogs suffering from it may refuse food and water due to intense nausea.
This is a potentially serious condition that requires veterinary care to manage pain, inflammation, and fluid loss.
Read more: Dog Diarrhea and Not Eating (Causes and when to worry)
Kidney Disease
Acute or chronic kidney disease can both result in nausea, vomiting, and loss of appetite.
Dogs may also urinate more or less frequently, show signs of fatigue, and stop drinking even though they’re becoming dehydrated.
Toxins and waste products building up in the bloodstream make them feel sick and uninterested in eating.
Toxin Ingestion
Consuming toxic substances (like chocolate, xylitol, rat poison, certain plants, or medications) can make your dog acutely ill.
Vomiting, drooling, staggering, and refusing to eat or drink are all common signs.
Depending on the toxin, effects can be rapid and severe, so early treatment is critical.
Parvovirus
Parvo is a highly contagious and potentially fatal viral infection, especially in puppies and unvaccinated dogs.
It leads to severe vomiting, bloody diarrhea, and total loss of appetite and thirst.
Dehydration sets in quickly, and without aggressive veterinary treatment, it can become life-threatening within days.
Stress or Motion Sickness
Dogs that are traveling, boarding, or undergoing major changes may experience nausea from stress or motion sickness.
They may vomit and avoid food or water until they feel secure or return to familiar surroundings.
While not always serious, this can still cause dehydration if it persists more than a day.
What to Do If Your Dog Is Sick and Not Eating or Drinking
If your dog refuses food and water, give them a quiet, comfortable place to rest and monitor them closely for changes.
You can try offering bland food like boiled chicken and rice or plain bone broth to tempt them to eat or hydrate.
Use a syringe (without the needle) to gently offer water if they won’t drink on their own, but do not force it if your dog is resisting or choking.
Keep their environment calm and free from stress or stimulation, and avoid giving treats or rich food during this sensitive period.
If your dog vomits multiple times or goes more than 24 hours without food or 12 hours without drinking, it’s time to take action.
When to Call or Visit Your Vet
You should contact your veterinarian if:
Your dog vomits more than once or has persistent diarrhea.
There is blood in vomit, diarrhea, or saliva.
Your dog refuses water for more than 12 hours.
You notice lethargy, trembling, bloating, or signs of pain.
Your dog has known medical conditions like diabetes or kidney disease.
You suspect they ingested something toxic.
Dogs can become dangerously dehydrated in a short time, especially small breeds, seniors, and puppies. Early treatment prevents complications.
Read more: Dog Seizure and Not Eating (Causes and what to do)
Key Takeaway
When your dog is sick and not eating or drinking, it’s a sign that their body is struggling with something serious — from infections and toxins to organ problems.
Pay attention to the duration and severity of symptoms, and offer gentle support at home when appropriate.
But never delay contacting your vet if vomiting, dehydration, or lethargy persist. Prompt care can make all the difference in your dog’s recovery.