Decreased appetite (hyporexia), or loss of appetite (anorexia) in dogs can be stressful for pet parents, and can often indicate an underlying medical condition. Anorexia for more than 24 hours should not be ignored, as it is often a warning that something else is going on.
Here’s some insight on why your dog is not eating, and some tips for what you can do to help.
Reasons Why Dogs Won’t Eat
There can be many reasons why a dog won’t eat, but they generally fall into three major categories:
Issues with the food itself
The list of possible medical causes for dog anorexia or hyporexia is very long and can include anything that might cause pain, nausea, lethargy, or stress:
Stomach upset (eating table scraps or something else they shouldn’t have, or a sudden change in food or treats)
Inflammatory bowel disease
Congestive heart failure
These are only some examples of medical issues that can lead to a loss of appetite in dogs; there are many more possible reasons.
Anxiety, stress, or fear can cause decreased appetite in some dogs, just like it can in people. Keep in mind that what you think is stressful is different from what your dog may see as stressful, and even small things can produce anxiety and cause them to not want to eat.
Changes in a dog’s routine or environment, such as new people or pets in the house, traveling, or loud noises such as construction, storms, or fireworks can trigger anxiety. Even something as simple as changing the time or location of a meal can cause more sensitive dogs to feel stressed, and it may make them less likely to eat.
Intimidation from another pet in the household can also cause a dog to avoid his or her food bowl. Many dogs do not like eating right next to housemates, as there can be intimidation that we, as humans, don’t pick up on. It is recommended that dogs be separated for feedings in order to decrease any resource guarding or intimidation.
Generally, if the issue is related to stress or anxiety, dogs will begin eating again after a day or two, once they have adjusted to the change. Some dogs may need behavioral modification or medical treatment to decrease stress and anxiety if it is frequent.
Issues With the Food
The issue might be with the food itself—it could be old, expired, stale, or spoiled. While some dogs, such as happy-go-lucky Labrador Retrievers, might eat anything in sight, others, such as Yorkshire Terriers, may be a little more particular.
If a dog has been on the same food for a while and has always eaten it well, take a look at the expiration date on the bag or can, and check to make sure that it is stored in an airtight container.
All dog food containers and bags should be sealed, and the food should be thrown out if the expiration date has passed. Open canned food can be sealed with plastic wrap or a lid that’s made to fit dog food cans, and it can be kept in the refrigerator for two to three days.
Many pet parents wonder if their dog may simply be tired of their food if they stop eating it. While some dogs may be picky, a healthy, hungry dog should not stop eating a certain food simply because they’ve eaten it for a while.
Sometimes it takes a few tries to figure out which dog food your dog likes best, but if your dog seems to get tired of food after food, it may be because they are getting too many treats or human food, or they might have a medical condition.
Dogs are smart and quickly learn that if they don’t eat their kibble right away, they might get some tasty treats instead. Rather than jumping right to table scraps or a new food, see if mixing kibble with canned food, or gently heating the canned food is helpful.
Switching foods suddenly often leads to stomach upset (decreased appetite, vomiting, diarrhea), so it can be very counterproductive. It would be very unusual for a dog to go hungry for several days just because they are picky, so it is important to rule out underlying medical conditions with your veterinarian if this happens.
Why Won’t My Dog Eat? Questionnaire
Use this questionnaire to help determine possible causes for your dog’s loss of appetite.
Will Your Dog Drink Water?
If your dog will drink water but won’t eat, it may be due to nausea, stress, or mouth pain. If they are able to keep the water down, that is a good sign. However, if they are vomiting after drinking water, they should be seen by a veterinarian right away, as this could indicate severe nausea or an intestinal obstruction. If they go longer than 24 hours without eating, even if they are still drinking, they should be examined by their vet to determine the underlying cause of their inappetence.
If your dog has not eaten or drank in 24 hours or more, they should be seen by a veterinarian right away in order to be assessed and treated for likely dehydration, and to investigate the underlying cause of their unwillingness to eat or drink.
Anything that can cause a dog to feel ill, such as kidney disease, pancreatitis, intestinal parasites, liver disease, cancer, infection, intestinal obstruction, etc., can lead a dog to refuse food and water. Like humans, dogs cannot go for more than a few days without water, so this should be treated seriously.
Does Your Dog Eat Treats But Not Food?
If your dog is refusing dinner but saying yes to treats or table scraps, they may be filling up on “junk food” rather than their own dog food. However, if your dog has other symptoms of not feeling well, a medical condition could be to blame for their altered appetite.
For example, if your dog is happy, energetic, drinking water, playing, and not having any vomiting or diarrhea, it may be that they are simply getting too many calories per day in treats and aren’t hungry for their meal. They may also have outsmarted you, knowing that if they refuse to eat their food, they’ll get tasty chicken and dog treats instead.
However, if your dog is lethargic, having any vomiting or diarrhea, starting to eat a bit then stopping, or drooling or licking their lips, they may not be feeling 100% well. Treats are higher rewards, so many dogs will be more likely to eat those rather than their food, even if they aren’t feeling the best. Think of a time when you’ve had an upset stomach but powered through to have your favorite treat while passing up the salad bar.
It is always best to be on the safe side and have any possible medical conditions ruled out if getting your dog to eat is becoming a frequent challenge.
Is Your Dog Not Eating Dry Food?
Does your dog turn up their nose at dry food, only to wolf down canned food the minute you set it down? This is a common complaint from pet parents, and it can mean a few different things.
It may be that your dog has dental or oral pain. Many pet parents believe that if their pet is eating, they must not have oral pain, but that’s not the case. They have to eat, so many dog struggle silently with oral pain for months or years until a dental procedure is done to extract any rotten or infected teeth.
While some dogs will still eat dry food even with severe oral pain, many prefer canned food, as it’s easier to chew. If your dog is no longer wanting to eat dry food but will eat canned, they should be seen by their veterinarian for an oral examination.
It may also be that your dog prefers canned food to dry food, as it often smells stronger and may be seen as more of a “treat.” Try mixing canned food with the dry kibble to encourage your dog to eat, and gradually transitioning to a higher ratio of dry food, until your dog is back to eating dry kibble.
Some dogs simply refuse to eat kibble in favor of canned food. While this can have some negative consequences, such as worse dental disease or a higher food bill, it may not be a problem to have your dog on canned food long-term. Talk to your veterinarian to see if feeding your dog an all-canned diet may be the best option for them.
Is Your Dog a Senior?
While senior dogs may have lower caloric requirements than young dogs, and therefore may eat less than they used to, marked weight loss or a refusal to eat is not normal and can indicate serious underlying health conditions.
These can include, but are not limited to:
Stomach upset (eating something they shouldn’t have or a sudden change in diet)
Cognitive decline, mobility issues, or vision loss can also cause a dog to not eat if they are unable to find or get to their food bowl. It is important for senior dogs to have a feeding routine, that the food bowl remain in the same area of the house so that they know where to find it, and that they have a rug or yoga mat to stand on while eating to avoid slipping or having trouble standing on hard floors.
If your senior dog has gone longer than 24 hours without eating, they should see their veterinarian for a thorough physical examination and possible diagnostics to investigate the cause of their loss of appetite.
Is Your Dog a Puppy?
A young, healthy puppy shouldn’t go more than a few hours without eating.
Small breed puppies, especially, are at a high risk of hypoglycemia (low blood sugar) and should be watched closely for signs of lethargy or collapse if they are not eating. If this happens, they should be treated on an emergency basis.
Some puppies may not like larger kibble, as it can be hard for their puppy teeth to chew, especially if they are just transitioning to solid food. This can be remedied by mixing in water and letting it soak to create more of a porridge consistency, or the kibble can be mixed with canned food as well.
If your puppy still will not eat, they should be seen right away by a veterinarian. If they are also lethargic, vomiting, or having diarrhea, they should be seen on an emergency basis.
Did You Just Adopt Your Dog Recently?
A newly adopted dog can take days or weeks to settle into their new home. Anxiety is a common cause of temporary inappetence, so it’s not unusual for a new addition to the household to refuse food for the first day or two.
It is important to ensure that they are given a quiet place to eat, away from other pets or children that may interrupt them. As long as they are otherwise energetic and not having vomiting or diarrhea, it’s okay to give them a day or two to get used to their new home before worrying about them not eating.
However, if they are lethargic, vomiting, or having diarrhea, or go more than 48 hours without eating anything, they should be examined by a veterinarian to rule out any underlying medical conditions.
Did Anything Change in Your Household?
Some dogs may be sensitive enough that a change in their environment may cause inappetence. Examples include a new addition to the family (whether a new pet or a new baby), construction, having people over, or even a change in the location of the food and water bowls.
While noise phobias aren’t specific to your household necessarily, things like thunderstorms and fireworks can also cause enough anxiety to discourage your dog from eating.
Could Your Dog Have Separation Anxiety?
Many dogs with separation anxiety refuse to eat while their pet parent isn’t home. Some dogs with separation anxiety even expect their loved one to be in the room while they eat, and will stop eating if their human leaves the room.
While this is not necessarily a health concern, it is a sign that your dog may have severe anxiety that needs to be addressed. Calming chews such as Composure or Solliquin may be helpful, and calming pheromone collars or diffusers such as Adaptil can be beneficial as well.
However, if you are concerned that your dog may have severe separation anxiety, consider consulting with a board-certified veterinary behaviorist for help.
Did You Switch Dog Foods?
Transitioning from one dog food to another too quickly can cause stomach upset, which may mean that your dog doesn’t feel like eating. It’s important to transition foods gradually over 7-10 days in order to avoid stomach upset. This also allows your dog to get used to the new food over time, rather than making a sudden switch.
Is Your Dog Pregnant or in Heat?
Early in pregnancy, your dog may have a reduced or absent appetite. If your dog is in the middle or late part of her gestation, she may eat less because her stomach has less room to expand due to the presence of puppies, but she should make up for this by eating a smaller amount more frequently.
Regardless of what point of gestation your dog is in, if she has not eaten in over 24 hours, your veterinarian should be called right away to ensure that everything is okay.
Dogs in heat may also have a decreased appetite, which is considered normal. However, if she goes longer than 48 hours without eating anything, she should be checked by her veterinarian. If she is lethargic, vomiting, having diarrhea, or drinking and urinating more than usual, she should be seen by her veterinarian right away, as this could indicate an infection in the uterus known as pyometra.
Is Your Dog Diabetic?
If your dog is diabetic and will not eat, this could be an indication that something is seriously wrong. Ask your veterinarian what they recommend doing if your dog won’t eat at the time of your dog’s diagnosis.
As a general rule, dogs should not be given as insulin if they aren’t eating, as this can cause dangerously low hypoglycemia. If your veterinarian advised you to give a half dose of insulin if your dog skips one meal, do so, but alert your veterinarian immediately if your dog skips another meal.
If your diabetic dog skips a meal, is lethargic, nonresponsive, or vomiting or having diarrhea, they should be seen by a veterinarian immediately, as this could be an indication of hypoglycemia or diabetic ketoacidosis, both of which are life-threatening if not treated right away.
Did Your Dog Just Have Surgery?
It is not unusual for your dog to skip a meal or two after a surgery. The medications used for sedation and anesthesia commonly cause nausea and a decreased appetite, and medications that they may go home on, such as pain medications and/or antibiotics can also suppress the appetite.
You may try tempting your dog to eat with a spoonful of canned food or boneless, skinless, boiled chicken on top of their kibble. Better yet, ask your veterinarian for a few cans of a prescription gastrointestinal diet to feed for the first few days after surgery. These foods are highly palatable, are easily digestible, and can help counteract some of the gastrointestinal upset that can happen after surgery and anesthesia.
If your dog had oral or facial surgery, your veterinarian may recommend feeding only canned food for two or more weeks. This also means that your dog should not receive hard treats or chew on hard toys until they are declared healed at their recheck appointment. If your dog is refusing to eat the prescribed canned food, reach out to your veterinarian in case there are any post-operative complications.
What to Do When Your Dog Won’t Eat
If your dog is lethargic, vomiting, or having diarrhea in addition to not eating, see your veterinarian right away. If you don’t see any of these, here are some ways to try to entice your dog to eat:
Add water or no-sodium chicken broth to the dog food and let it soak for several minutes to soften it.
Heat canned food for a few seconds in the microwave (make sure to take it out of the metal can and put it into a microwave-safe bowl). Canned food can become scorching hot quickly, so feel the food first to avoid any burned tongues.
Try mixing some plain, boneless, skinless boiled chicken and rice with their kibble to encourage them to eat.
Add a probiotic such as Purina Fortiflora or Advita on top of the food. Not only can this make the food more palatable, but it can also help any inflamed or irritated intestine heal by rebalancing a healthy gastrointestinal flora.
If you have tried these tricks and your dog continues to refuse his food, he should be seen by his veterinarian to rule out any underlying medical conditions.
Unless explicitly prescribed by your veterinarian, your dog should not be given any over-the-counter gastrointestinal medications like Imodium or Pepto Bismol, as these could cause serious side effects or even interact with medications that your veterinarian may want to give. It is best to consult with your veterinarian before attempting to treat symptoms at home.