Sad dog and food bowl

Why My Dog Won’t Eat: 6 Reasons

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A common but worrying situation that dog owners may face is when their dog won’t eat. Poor appetite in dogs is a vague symptom that can occur for many reasons, some more serious than others. Read on to learn about the potential causes of inappetence in dogs, and find suggestions for what you can do to help.

Oral Pain

Dogs may stop eating if chewing or swallowing is causing discomfort. Dental disease (gingivitis and periodontal disease) is the most frequent cause of oral pain in dogs, since it is seen so commonly.1

Gingivitis causes gum inflammation and recession, exposing the sensitive roots of the teeth. Periodontal disease causes gradual loosening and loss of teeth in a slow and painful process.2 Brushing your dog’s teeth daily and scheduling yearly dental cleanings can help to reduce dental disease.3 Other potential causes of oral pain include jaw or tooth fractures, ulcerations or lacerations of the gums or tongue, and oral tumors, to name a few.4


Nausea is another common reason for a loss of appetite in dogs. Just like humans, dogs often won’t eat if they feel they need to vomit. Causes of nausea in dogs are many, and include gastrointestinal illnesses (eg, gastroenteritis, intestinal parasites, pancreatitis, etc) or systemic disorders (liver diseases, kidney diseases, Addison’s disease, etc). In addition to refusal to eat, panting, restlessness, excessive drooling and/or swallowing, lip licking, dry heaving, and vomiting can all be signs of nausea in dogs.56

Other Illness or Injury

Many other conditions can cause dogs to have a poor appetite. Severe infections causing significant discomfort, fever, or malaise can make dogs stop eating.7 Tickborne illnesses such as Lyme disease, Anaplasma, and Ehrlichia, among others, can also cause decreased appetite.8 Certain types of cancers may be associated with poor appetite, especially in more advanced stages.9 Essentially anything causing significant discomfort to a dog, whether illness or injury, can potentially affect its desire to eat.


People often eat more or less than they usually would when experiencing stress. In the same way, anxiety or stress may also affect dogs’ appetites. Dogs may experience stress for many reasons, such as changes to the household (new people, animals, or objects, construction, moving, etc), loud noises (fireworks or thunder), large gatherings, etc.10 Some dogs may also have anxiety disorders; for example, dogs with separation anxiety commonly will not eat unless someone is home with them.11 Often, identifying the source of stress or anxiety and mitigating or removing it will improve the dog’s appetite.


While many dogs will eat all their food and then beg for more, some will not eat more than they truly need in a day. This is called self-regulating, and owners of dogs that do this will often incorrectly believe their dog isn’t eating enough. This is because overfeeding our dogs is very common. We may offer them too many treats, supplement their dog food with unnecessary table food, or feed more dog food than the necessary amount.12

Feeding guidelines on dog food bags are often inaccurate because they are calculated to meet the highest necessary energy requirement for each weight class.13 In other words, owners may be feeding their lazy Labrador the same amount of food needed by an Alaskan sled dog running the Iditarod; obviously, the Labrador is receiving more calories than it needs in this scenario.
The best way to know how much food your dog needs per day is to ask your vet to calculate this for you based on your dog’s weight, life stage, and normal diet. This website may be helpful for owners wanting to try this calculation as well.

Holding Out for Something Better

Sometimes our dogs train us better than we train them. For example, if your dog learns that refusing their dog food now means they’ll be offered treats or table food later, the dog will often hold out for the better food option.14

Tough love may be the way to go in this case. Don’t offer treats or human food if your dog doesn’t eat within a few hours. Instead, you can try adding warm water to the food, warming up wet food or moistened kibble, or pretending to eat the food yourself and then offering it to the dog.

If these methods are unsuccessful, you may try a different flavor or type of food, mix in a small amount of wet food to dry kibble, or, if absolutely necessary, mix very small amounts of bland, low-fat human foods like boiled chicken breast or steamed green beans into the dog food. A well-balanced dog food should be the mainstay of the diet.

What Should I Do if My Dog Stops Eating Normally?

Dogs that stop eating normally should be examined by a veterinarian as soon as possible, especially if they refuse to eat anything for more than 24 hours or are having additional signs like tiredness, weakness, limping, vomiting, diarrhea, or bloody stool. Young puppies and diabetic dogs should see a vet immediately if they miss more than one meal.

As discussed above, poor appetite can be a sign of underlying illness or pain. Though it may be tempting, avoid feeding your dog treats or fatty human foods to get them to eat, as this can make certain conditions worse. Instead, call your veterinarian, who can often provide safer dietary suggestions for dogs that aren’t eating well.

Article Sources

Pets Digest uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

  1. Lewis J. How to spot signs of oral pain in your pet patients. Published February 13, 2017. Accessed July 27, 2022.
  2. Hiscox L, Bellows J. Dental disease in dogs. Accessed July 27, 2022.
  3. Barnette C. Dental pain in dogs. Accessed July 27, 2022.
  4. Reiter AM. Dental disorders of dogs. Updated October 2020. Accessed July 27, 2022.
  5. Williams K, Ward E. Vomiting in dogs. Accessed July 27, 2022.
  6. Webb CB. Vomiting in dogs. Updated October 2020. Accessed July 27, 2022.
  7. Llera R, Downing R. Anorexia in dogs. Accessed July 27, 2022.
  8. American Kennel Club Canine Health Foundation. Tick-borne disease: prevalence, prevention, and treatment. Accessed July 27, 2022.
  9. American Veterinary Medical Association. Cancer in pets. Accessed July 27, 2022.
  10. Llera R, Downing R. Anorexia in dogs. Accessed July 27, 2022.
  11. Amat M, Camps T, Le Brech S, Manteca X. Separation anxiety in dogs: the implications of predictability and contextual fear for behavioural treatment. Anim Welf. 2014;23(3):263-266. doi:10.7120/09627286.23.3.263
  12. Gilbert S. Are you overfeeding your dog or cat? Accessed July 27, 2022.
  13. Freeman LM. Feeding frenzy: how accurate are your pet food’s feeding directions? Published April 22, 2019. Accessed July 27, 2022.
  14. Bauhaus JM. Dogs & table food: why to avoid feeding them scraps. Published February 14, 2020. Accessed July 27, 2022.
Dr. Jennifer Masucci
Dr. Jennifer Masucci
Dr. Jennifer Masucci, VMD is a graduate of the University of Pennsylvania School of Veterinary Medicine. Through multiple years of working as a small animal general practitioner, Dr. Masucci is particularly well-versed in canine and feline medicine. Dr. Masucci is passionate about educating pet owners, so that they can offer the best care to their furry companions.