When your dog won’t eat, it’s kind of a head-scratcher. You wonder: Is he sick? Is he bummed? Or is he just holding out for something better? Unfortunately, there isn’t a clear-cut answer—the list of things that can cause dogs to lose their appetites is nearly endless, says Christine Brennan, DVM, medical director of VCA Raleigh Hills Animal Hospital in Portland, Ore.
It’s OK to wait a day or two to see if your dog starts eating again as long as your pooch is still drinking water and not having other concerning symptoms like vomiting or diarrhea. In the meantime, read on for some help troubleshooting to see if there’s something you can do at home to help.

4 Common Reasons Why Dogs Won’t Eat
1. Your dog doesn’t like their food.

Some reasons why dogs refuse to eat are easy to fix like their food has gone bad or they don’t like the flavor of a new kibble. It might be that they can’t stand eating next to other dogs in the home. In those situations, you can make sure the food is fresh or swap it out with a different brand, and separate dogs during feeding time.

2. Your pup is experiencing side effects from a medication.

New medications can also make dogs lose their appetites. Some drugs have nausea as a side effect. A new prescription diet might be to blame too. They aren’t always the tastiest. If you think that’s the case for your dog, consult with your veterinarian about the next steps. Maybe you can switch to another medication or prescribed diet or use a tempting treat to get your pup to eat.

3. Your dog is feeling anxious or sad.

Dogs are also emotional creatures. They may stop eating if they’re anxious or upset. Changes like a move to a new home, being kenneled while you’re on vacation, a death in the family or even kids returning to school can make a dog feel blue.

4. Your dog is sick.

Other times, dogs don’t eat because they’re ill. “Dogs often stop eating when they’re in pain,” says Brennan. “Common causes include intestinal parasites, eating food that disagrees with them or eating a foreign object like a toy, bone, or sock. But it can also be from a systemic illness such as cancer.”

Is Your Dog Not Eating Food But Still Drinks Water?

If your dog avoids chewing hard kibble but drinks water, he might have mouth or dental pain. But it could still be a number of other things too. “Thirst is a powerful natural force,” Brennan says. “Even nauseated dogs may still want to drink when they’re dehydrated.”

Some illnesses even cause increased thirst, like urinary tract infections and endocrine disorders such as diabetes. An exam and lab tests including blood work and urine and fecal samples can help your vet get to the root cause.

Is Your Dog Eating Grass?

It’s a myth that dogs only eat grass when they’re feeling sick, says Brennan. “A large percentage of healthy dogs on a well-balanced diet eat grass and only a very small number of them vomit after eating it. Many like the taste or do it out of instinct, anxiety, or perhaps the need for more fiber,” she explains.

But it does become worrisome if your dog is refusing food but eating grass. It could be related to discomfort or disease in your pooch’s stomach or intestines. In that case, Brennan recommends reaching out to your veterinarian to find out if you should come in for an exam.

Is Your Dog Throwing Up and Not Eating?

A dog not eating becomes more serious if there are additional symptoms like vomiting or diarrhea. It could indicate a condition that’s worsening and your dog may need medical attention sooner rather than later.

Is Your Dog a Puppy?

If a puppy won’t eat, it’s more likely due to a case of parasites or to consuming something they shouldn’t have like a rock or a shoelace, shares Brennan. “We certainly do far more surgeries to remove foreign objects from young dogs than from old ones.”

Because puppies younger than six months can’t go as long without eating as older dogs, they need to be seen sooner. If your puppy hasn’t eaten for 12 hours, take her to the vet as soon as possible.

Is Your Dog a Senior?

As dog’s age, they tend to slow down and eat less but they should still be eating regular meals. Senior dogs are more likely to stop eating entirely due to an ongoing illness that’s worsened, says Brennan.

Possible causes include dental problems, heart disease, intestinal issues, or diseases like cancer. It’s important to have your old pal examined by a vet to find out what’s causing the problem and the best way to treat it.

How to Stimulate a Dog’s Appetite to Get Them to Eat More

The go-to for getting dogs to eat is to make their chow super enticing. That also means scaling back on treats so your pooch is hungrier when it’s mealtime. Make kibble softer and more aromatic by adding warm water or broth. You can also try offering your dog canned food if he normally eats dry food or cooks his favorite dog-safe human foods and give them in small amounts.

“However, if you haven’t found out what’s wrong and corrected it, you’re fighting a losing battle,” states Brennan. “You should see your veterinarian find out what’s really going on and how to get your dog’s appetite back to normal.”

Source: https://www.dailypaws.com/dogs-puppies/dog-behavior/dog-not-eating