Signs Your Dog Is Sick

Reviewed by Dr. Fiona Lee

Your dog normally trots to the door when she sees the leash, eagerly eats dinner and never has accidents in the house. But things have changed, and your happy and well-behaved dog has started showing some unusual (or even naughty) behaviors. Before you resort to calling her a “bad dog" and taking away toys, consider this: Your dog not acting normal could be a sign of something wrong—and sickness might be to blame.

But how do you tell if your dog is sick? Look for these possible symptoms and signs that a dog is sick.

1. Increased or Decreased Urination

House training your dog was a breeze, and he hasn't left a puddle on the living room rug in ages—until now. You might think that your perfectly potty-trained pup is peeing in the house to punish you for a long workday or refusing to serve up a second supper, but something else may be going on.

Potty accidents can be a sign of medical issues. Kidney disease, tumors, infections and spinal cord injuries can all cause incontinence, and certain medications could also be to blame. In senior dogs who already struggle to hold their bladder for long periods, hormonal changes can cause an increase in thirst, which in turn can create more urine, triggering accidents or incontinence.¹

Watch for the following sick dog symptoms regarding urination:²

• Straining to urinate
• Changes in urine volume (an increase or decrease): Increased urination may be a sign of an issue with the kidneys or even diabetes mellitus.³
• Blood in the urine: Bloody urine can be a sign of a urinary tract infection, bladder stones or blood problem, or a more serious condition like cancer.

If you see any of these signs of dog sickness, book an appointment with your vet ASAP for a checkup.

2. Vomiting or Diarrhea

It happens: Dogs sometimes throw up or have loose stools. But this can also be a sign of a sick dog.

If your dog has one round of vomiting or diarrhea but is otherwise acting and eating normally, it may just be an upset tummy. Monitor symptoms and feed small portions of bland, wet food (such as boiled chicken or cooked hamburger mixed with rice) for a day or two until symptoms improve. Then, gradually reintroduce dry food.

But if these sick dog symptoms continue within or beyond 24 hours and are accompanied by other symptoms (such as weakness, lethargy, loss of appetite or dry heaving), book an appointment with your vet. It could be a sign of something more serious, such as a foreign object that was ingested, viral or bacterial infection or parvovirus infection in puppies.⁴

3. Whimpering

Since your dog can't tell you where it hurts, they might turn to their only method of communication: vocalizing. A dog that whines or whimpers when getting up and down from their dog bed, grunts while going up or down the stairs or barks more often could be communicating that something hurts.⁵

4. Poor Appetite

Loss of appetite can be a sign of a dog not feeling well. However, the level of concern for this symptom largely depends on how food-motivated your dog is. For example, for a dog who normally doesn't finish meals, this may not be that concerning. But for a dog who never misses a meal, this may be an indicator of an underlying illness.

Try feeding your pup a little bit of cooked chicken or hamburger or offering some tasty treats to entice them. If they're still not eating normally after a day or they're showing other symptoms (like lethargy, vomiting and weakness), see your vet.

5. Excessive Panting

Panting helps dogs cool down when they're feeling overheated, but constant and intense panting can be a sign that something is wrong with your dog. For instance, your dog may be experiencing heatstroke or a painful injury, or they may have consumed a toxic substance. Serious illnesses—such as heart failure, Cushing's syndrome or respiratory disorders—can also trigger heavy panting in dogs.⁶

If you suspect heatstroke, take the following steps right away:⁶

• Move your dog inside or into the shade and offer water.
• Immerse your dog's feet in cool (not freezing cold) water or wrap cold towels on your dog's chest, neck and head.
• Give your dog cool (not ice cold) water or ice cubes to lick.
• Get to the vet as soon as you can, as heatstroke requires immediate attention.

If you suspect that something else may be at play, book an appointment to see your vet as soon as possible.

6. Coughing or Breathing Problems

Coughing, wheezing, breathing difficulties and nasal discharge can be signs of a cold virus or dog allergies. However, these sick dog symptoms may also indicate something more serious, such as canine flu, kennel cough, tracheal collapse or heart disease.⁷ If respiratory symptoms continue or are accompanied by other symptoms such as lethargy, book an appointment with a vet.

If your dog struggles to breathe or her tongue and gums look bluish, treat this as a medical emergency and get to the clinic right away.

7. Low Energy or Difficulty Waking or Getting Up

Dogs are serious sleepyheads that can spend as much as 50% of their days asleep, so it may be normal to find your dog snoozing on the sofa or lounging on the linoleum.⁸ However, a noticeable change in their exercise regimen or a dog that doesn't want to exert energy can be signs of a dog not feeling well.

Lethargy is an all-too-common sign of illness in dogs, and it can turn a dog that loves daily walks into one that doesn't want to get out of bed. Plenty of illnesses—from parvovirus and diabetes to hypothyroidism and heart disease—can cause lower energy levels.⁹ Make an appointment with your vet to get to the bottom of their newfound laziness—even if you have to drag your dog out of bed to get them to the clinic.

8. Pale Gums

Healthy dogs have pink, moist gums (except for pigmented portions, which can be black). If the pink portion of your dog's gums is pale, it could be a sick dog symptom. If your dog has pale gums and is also lethargic, weak or struggling to breathe, consider it a medical emergency and get to the clinic.¹⁰

9. Red, Runny, Sticky or Puffy Eyes

Your dog's eyes can be a window into how they're feeling. Red eyes, eye discharge, squinting, puffy eyes or sticky eyelids can indicate a range of possible health problems, from allergies to dog conjunctivitis to glaucoma. If your dog is pawing or rubbing at their eyes, take your dog to the vet.¹¹

10. Abnormal Behavior

A dog not acting normally can indicate that a dog is sick. Here are a few unusual behaviors to watch for:

Hiding

If your dog scoots under the bed or hides in the closet, it may not be because they're avoiding the bath or nail trims. Dogs often seek out secret locations to mask illness or injury. Look for other signs that your dog isn't feeling well, which can include excessive panting, whimpering, trouble walking, poor appetite, vomiting or other abnormal behaviors. Fear and anxiety can also cause your dog to seek a safe space to hide.¹² If the hiding is a new behavior, veterinary attention is warranted.

Refusing contact or snuggles

Is your dog ignoring your requests to hop up on the couch? Does she move away when you offer belly rubs? In some cases, ignoring commands, taking a defensive posture when you approach or growling when touched can indicate discomfort with physical contact—which can also be a red flag for illness.⁵

Dogs that are in pain can be sensitive to touch. Rule out underlying chronic pain, illnesses or injuries that could make your dog flinch, growl or shudder when you try to pet them or snuggle.¹³

Clingy behavior

Some dogs may become clingy or needy when not feeling well. If your dog is normally pretty self-assured and independent but suddenly becomes your shadow, this could be a sign that something is wrong.

Aggressive behavior

If your normally nonaggressive dog shows aggression—biting, snarling, snapping or growling—for no apparent reason, there could be an underlying medical condition. Infectious diseases (such as rabies), hormonal imbalances, psychomotor epilepsy, hyperkinesis, neoplasia and a variety of genetic and metabolic disorders can be linked to dog aggression.¹⁴ Always look out for your safety when handling a dog that seems prone to aggression.

Also, painful conditions (such as dental disease or arthritis) and medical conditions causing fever, fatigue or sensory loss might trigger aggression in dogs.¹⁴

Whatever the behavior, your vet can do a thorough physical exam to help figure out why your normally outgoing and affectionate pup has been acting differently.

11. Scooting

No one loves to watch their dog scoot their bottom across the floor. The behavior is gross, but it's also a completely normal way for dogs to address an itchy backside.¹⁵

When scooting goes from an occasional occurrence to a regular behavior—and no amount of saying, “Stop that!" prevents it—pay attention. Dogs scoot when their anal glands are full; scooting can also be a symptom of an infection or abscess causing swelling near the anus, an anal gland mass, tapeworms or other parasites or allergies.¹⁵

Scooting that's accompanied by painful bowel movements, straining to defecate, an increase in itchy skin, licking and biting at their backside, foul odor from their rear end or matted hair warrants a trip to the vet to get to the “bottom" of the problem.¹⁵

12. Eating Poop

There's nothing that makes a pet parent shout, “Bad dog!" faster than spotting their favorite four-legged companion eating poop. The technical term for this behavior is coprophagia in dogs, and it's more common than you might think. However, it could be a sign of an illness called malabsorption syndrome, which causes dogs to turn to feces as a food source to ingest more calories.¹⁶

Aside from the obvious “ick" factor, there are some serious risks to eating poop, including potential parasite infestation. Take your dog to the vet to rule out underlying issues that could be causing coprophagia.¹⁶

Tips To Keep Dogs Healthy

While it's essential for pet parents to recognize the signs that their four-legged companions aren't feeling well, it's also important to know how to keep them healthy.

Healthy diet

Dogs need foods that offer the right balance of proteins, fats, carbohydrates, vitamins and minerals. Whether pet parents choose canned food or kibble, look for brands with the Association of American Feed Control Officials (AAFCO) seal that indicates the food has the right balance of nutrients.¹⁷

Exercise

A dog's breed, age and health will determine how much exercise a dog needs.¹⁸ Dachshunds might be satisfied with a quick dash around the block, while Border Collies need lots of long walks (or runs).

Regular exercise gives dogs a chance to stretch their legs and explore their environment. It provides mental stimulation and can help reduce the risk of obesity and extend their lifespan.¹⁸

Preventives

Fleas and ticks aren't just gross—the petite parasites can cause health issues such as skin irritation, tapeworm and Lyme disease. Preventives, which include topical and oral medicines, can prevent flea and tick infestations and keep your pet healthy. Your vet can recommend the best preventive medications for your dog.¹⁹

Heartworm prevention is also essential. Mosquitoes carry the disease and can transmit it to dogs, leaving hundreds of worms in their heart. The worms can cause damage to the heart and lungs, triggering symptoms like coughing, fatigue and decreased appetite. Heartworm disease can be fatal—but it's preventable.²⁰

Routine vet visits

Vet care is important when pets are sick and when they are well. Regular wellness visits include physical exams and might also involve blood work, urinalysis, vaccines and other screenings.²¹

The information allows your veterinarian to establish a baseline, uncover the signs of early disease and detect age-related changes (and recommend medications or changes to diet or lifestyle that could help).²¹

FAQ

How to tell if a dog has a fever? What are dog fever symptoms?

Dogs have a normal temperature range of 99.5 to 102.5 degrees Fahrenheit. You can use a pet thermometer to take your dog's temperature. Watch for dog fever symptoms like lack of energy, shivering, warm ears, warm and dry nose, shivering, coughing, vomiting and loss of appetite.²²

My dog's nose is running. Are they sick?

A dog runny nose could mean many things. Clear discharge could be caused by allergies, while mucus or pus—especially if it has a bad odor—could be a sign of infection, polyps or a tumor. It's best to make an appointment with your vet if your dog's nose is running.²³

My dog sounds congested. Is that part of dog cold symptoms?

Dog congestion can include nasal discharge, trouble swallowing, sneezing, snoring and other symptoms. It could be caused by a respiratory infection or other health issues such as allergies, kennel cough, dental disease or tumors. Make an appointment with your vet to get an accurate diagnosis for dog congestion.²⁴

My puppy has a warm nose. Is that a sign of sickness?

A dehydrated puppy could have a dry nose, but in general, a warm nose isn't a sign of illness. The temperature of your dog's nose can change all the time. Instead of relying on how your dog's nose feels to determine if they are sick, look for other signs of illness like changes in their eating, drinking patterns or behaviors.²⁵

Pets Best Is Here to Help

No pet parent wants to learn that their normally upbeat and healthy furry friend is sick. When behavior changes are a potential sign of illness, make a vet appointment to get your dog feeling better and address their illness-related behavior changes. But the costs of medical care can add up, with the average cost of an annual wellness visit for dogs totaling $214, plus the added costs to treat chronic conditions, illnesses or injuries.²⁶

A pet insurance policy can help provide peace of mind. Pets Best insurance policies include access to a 24/7 Pet Helpline to get answers to your questions via phone, live chat or email. You can even pay your vet directly so you're not waiting to be reimbursed.

This comprehensive coverage helps ensure that you can get your dog the treatment they need—so you can focus on enjoying time with your best buddy, not worrying about the vet bills. Start shopping for a policy at Pets Best.

Sources/ Citations

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