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How Do You Know a Dog Is Sick

↯ Key takeaway points

  • Dogs cannot communicate when they are sick, so it is important to monitor their health regularly
  • Vaccinations and deworming can prevent many illnesses in dogs
  • Proper nutrition, including protein, fats, carbohydrates and vitamins, is essential to keeping dogs healthy
  • Regular exercise is important, but overexertion can cause fatigue
  • Changes in eating habits, breathing levels, and lethargy lasting longer than usual are signs that a dog needs urgent medical attention
A pet lover passionate about educating readers about animal health and care. Love reading studies and recent research.
Zoo and wildlife doctor in veterinary medicine passionate about animal welfare and preventive medicine.
Published on
Monday 3 October 2022
Last updated on
Tuesday 30 May 2023
How Do You Know a Dog Is Sick
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Dogs don’t speak, so they can’t tell you if they’re sick. Instead, you have to be vigilant in assessing their health. When a canine shows signs of disease, it shouldn’t be taken lightly. Whether it be a sudden state of lethargy or abrupt changes in body odor, all of those require urgent medical care.

Yet, there are also times we mistake normal body changes with illnesses. If you want to know how to tell if your dog is sick, then look at this article.

18 Common Signs and Symptoms of a Sick Dog

A dog’s health can sometimes be deceiving. What we think is normal can be life-threatening. As pet owners, we need constant monitoring of our dog’s health. This article listed the top 18 most common signs and symptoms of a sick dog. Check them out below.

1. Repeated Vomiting or Gagging

Throat blockage is common in dogs. Dogs swallowing solid foreign objects can get stuck in their throats. So, the only thing that can get them out is to gag and vomit.

In some instances, sick dogs suffer from laryngeal paralysis. This condition happens when the cartilages of the voice box don’t function properly. The cause of this illness can be due to infections, trauma, or tumor.

Dogs, if untrained, will have no control over food. Vomiting and gagging are caused by an upset stomach. Hence, dogs who eat leftovers and fatty food are prone to this.

2. Diarrhea

If you notice your dog has a watery poop, then that’s not normal. Another sign of a dog not feeling well has intestinal parasites that cause diarrhea and bloating. To avoid this, ensure your dog has updated deworming and vaccine sessions. 

Diarrhea can be caused by an inflammatory bowel disease as well. Until now, IBD cannot be completely cured but is only manageable by medicine. Certain factors such as genetics, bacteria, and low immune systems contribute to this illness. 

Kidney and liver damage also cause chronic diarrhea, weight loss, and vomiting. Unfortunately, if left untreated, this disease can be life-threatening.

3. Drooling and Bad Breath

The most common way to tell if your dog is sick is to check for changes in drooling. Excessive drooling, also known as hypersalivation, can be caused by the rabies virus. Small dogs usually have dental or gum disease. They are the most prone to experience drooling and bad breath. Yet, chronic bad breath can also be due to respiratory and gastrointestinal problems.

Persistent bad breath can be a sign of oral melanoma. Without treatment, dogs with this disease can only live up to 65 days. Although, with surgery, the lifespan could be lengthened for about a year.    

4. Increased or Decreased Urination

Excessive urination is a warning sign of canine diabetes. Due to the high blood sugar, dogs produce excess urine, which causes frequent urination. Diabetes occurs when there’s not enough insulin in the pancreas.  

Another sign that your dog is sick is decreased urination. Straining leads to urinary tract infections or bladder stones. UTI occurs when bacteria enter the urethra and begin infection. Whereas bladder stones happen when minerals crystalize and cause blockage.

In severe cases, no urine is produced in a dog’s body. This condition is called anuria. Its possible causes can be a shock, blood loss, dehydration, or kidney failure.

5. Sneezing or Coughing

Canines can suffer from occasional influenza virus or also called dog flu. The symptoms of this dog sickness involve fever, coughing, sneezing, and lethargy for up to 3 weeks. Other times flu is mistaken with kennel cough. The main difference is that kennel cough is caused by Bordetella bacteria.

Meanwhile, parasites such as lungworms, roundworms, and hookworms travel to the lungs and cause dry cough.  Also, chronic coughing and wheezing can be due to congestive heart failure. This condition happens because of the fluid build-up in the lungs; if not treated early, it can be deadly.

6. Excessive or Restrained Drinking

Excessive drinking of water or polydipsia is a common dog sickness symptom. This condition is linked to Cushing’s syndrome, diabetes, or even kidney failure. 80 to 85% of dogs who suffer from Cushing’s disease have a tumor on the brain’s pituitary gland.

If dogs don’t drink water, they are at risk for dehydration. Canines with reduced thirst also suffer from underlying factors like bladder and urinary tract infections. Dehydration is a lot more serious than it seems. In worst cases, when dogs lose more water output, it could lead to kidney failure and death.

7. Appetite Change

Changes in appetite allow you to know if your dog is sick. Usually, loss of appetite is driven by external factors such as food selection or lack of motivation. Other times, it could signify serious illnesses such as liver damage, bacterial and viral infections, or even cancer.

No matter what, a dog’s loss of appetite cannot be taken lightly. Infections like parvovirus and distemper contribute to starvation. Both infections cause depression, diarrhea, vomiting, and loss of appetite. Also, they’re severely contagious and, if not treated early, can cause damages that lead to death.

8. Red, Pale, or Swollen Gums

A dog’s normal gum color should be pink. Yet, sometimes it changes color due to certain illnesses. For starters, Bright red gums indicate heat stroke or carbon monoxide poisoning. Whereas, Pale gums show that a dog has anemia. Blood loss from intestinal parasites leads to the paleness of gums as well.

Meanwhile, Blue or purple gums show your dog has heart disease or hypothermia. Another way to tell if your dog is sick is to check if he has red, swollen gums. The swelling indicates gingivitis, a condition where gums have excess growths and bleeding. 

9. Difficulty Urinating

You can tell if your dog is sick if it has difficulty passing urine. Factors like cancerous tumors block the pathway of urine too. In males, prostate gland infections can cause difficulty in peeing. Spinal cord injuries make dogs lose control of their lower limbs. As a result, they cannot urinate properly.

In rare cases, genetics play a vital role in a dog’s peeing routine. A condition called phimosis occurs when the sheath opening of dogs is narrow. When this happens, urine cannot pass down easily and remains inside the sheath. If not treated by surgery, it can result in infections. 

10. Change in Activity Level

Changes in activity levels can be due to low blood sugar levels or hypoglycemia. In dogs, low sugar levels lead to muscle weakness and seizures.

Weakness in dogs isn’t always a symptom of sickness. Deworming pills and vaccinations induce temporary loss of energy too. Other side effects also include stomach upset, loss of appetite, watery poop, and vomiting.

In other instances, a drop in energy levels is due to anxiety. If a dog feels anxious or stressed, it will always feel tired. Changes in the environment are also a factor that contributes to stress and anxiety.

11. Sudden Weight Loss or Gain

Intestinal parasites suck bodily nutrients, so dogs keep on losing weight. In other cases, those parasitic worms give a pot-belly appearance making it look like your pet has gained weight. Also, kidney failure triggers a drastic weight loss. Factors such as exercise, depression, and feeding schedule also contribute to weight loss.

One of the most unnoticeable symptoms of sickness in dogs is weight gain. Poor diet and lack of movement can cause unhealthy weight gain or obesity. Also, hypothyroidism and Cushing’s disease are two of dogs’ main contributors to slow metabolism.

12. Runny Eyes or Nose

A dog’s runny eyes or nose can be caused by factors such as nasal blockage, infection, or allergies. Foreign objects like grasses or seeds can be trapped inside a dog’s nose. When that happens, a bloody discharge comes out, which signals an infection.

You will know a dog is sick when looking at its eyes. A green mucus or watery discharge indicates conjunctivitis. Yet, conjunctivitis also links to other health problems such as distemper, allergies, and tumors. Plus, foul discharge can also be caused by genetic anomalies, like prominent eyes and glaucoma.

13. Itchy and Flaky Skin

Canines with itchy and rough, flaky skin have a condition called seborrheic dermatitis. It’s a skin illness that causes glands to produce more sebum. As a result, the skin becomes red, scaly, and itchy. Most of the time, it affects a dog’s face and back.

Meanwhile, hair loss is another way to tell if your dog is sick. Dry and itchy skin is caused by Demodex canis or red mite. Most dogs have these mites and yet pose no health concern. Sometimes, they can multiply quickly and inflame a dog’s skin.

14. Stiffness or Difficulty Climbing or Jumping

Legg-Perthes disease is a rare illness that typically affects the bones of small dogs. This shows signs of stiffness in the rear limbs, muscle atrophy, and limping. This only occurs when the blood supply on the top of the femur bone is cut off.

You can also tell if your dog is sick by observing its ability to move or jump. Cruciate ligament damage is a painful orthopedic condition that can be treated with or without surgery. If you notice your dog limping and having difficulty jumping, its ligaments must be torn.

15. Change in Behavior

At one glance, you can identify the symptoms of a sick dog by its behavioral changes. For instance, sick dogs may suddenly become aloof or energetic pet that gradually shows aggression over simple things. Dogs have low pain tolerance. That’s why they show inactivity when they’re in pain.

These symptoms don’t speak for all dogs in general. In other cases, some injured or sick dogs may get extra clingy. Being sick and in pain is a vulnerable situation for dogs. As a result, they may want to seek comfort from their owners.

16. Lethargy

Lethargy is a common symptom of a sick dog in the household. Most of the time, dogs feel down because they’re simply bored. But, if that situation goes on for longer periods, then it’s something serious. In worst scenarios, that lethargy could be cancer or organ failure.

Inactivity in dogs can be age-related. For example, senior dogs may get more tired than usual since their bones are weak. Also, weakness may occur if they’re poisoned or infected with leptospirosis. Dogs who like playing with dirty water are at risk of contamination. Further, if left untreated, it causes kidney and liver damage.

17. Frequent Sleeping

Dogs who are injured or in pain may feel tired more than usual. Sick dogs use sleep as a method to quickly heal their injury. So, as pet owners, we should provide our dogs with a nice and comfortable bed to sleep in. Canines with arthritis need an orthopedic bed to ease their swelling joints.

Another reason why injured dogs like to sleep is to conserve energy. That’s their bodies’ natural reaction to cope with illness. By doing that, they repair tissues and prevent further injuries from happening. So, the best that you can do to help is to lessen distractions.

18. Trouble Breathing

Labored breathing or Dyspnea is also one of the ways that tell if your dog is sick. Acute respiratory distress syndrome is common in dogs with lung infections. ARDS happen when blood vessels explode and leak into the air sacs. Its main causes are pneumonia, pancreatitis, and chest injury.

In some cases, dogs have trouble breathing because their airway is blocked. This can happen if they have blood clots, an infection, or swallowed something solid. Also, excessive panting or trouble breathing can be caused by fever, thyroid disease, or high blood pressure.

How to Keep Your Dog Healthy

To protect your dog from various diseases, vaccination is necessary. Vaccines for diseases like parvovirus, distemper, and rabies are available. Parasites can also affect dogs, and to prevent infection, regular deworming is crucial.

A balanced diet is essential for a dog’s health. Research has shown that dogs need three main components in their diet, protein, fats, and carbohydrates, to provide them with the necessary energy. Additionally, dogs require adequate amounts of vitamins A, D, E, and thiamine.

Exercising your dog regularly is an excellent way to maintain their physical and mental well-being. Lethargy is a common symptom of sick dogs, so it is crucial to avoid overexerting them during exercise. A training session of 30 to 60 minutes is ideal for your furry friend, any longer than that can lead to fatigue

When to Take Your Dog to the Vet

It’s important to take your dog for regular veterinary check-ups even if they seem healthy. Additionally, keep an eye out for changes in your dog’s eating habits and breathing levels as these can indicate sickness. If you notice any signs of illness, don’t wait until they worsen before seeking medical attention.

However, not all changes in behavior require veterinary treatment. Sometimes, dogs may seem uninterested or bored due to changes in food or anxiety. In these cases, it’s helpful to find ways to stimulate your dog, such as adding exciting games to your routine.

However, if your dog continues to show lethargy for extended periods or exhibits symptoms such as whining, limping, eye discharge, or skin rashes, it’s crucial to seek urgent medical care.

Remember, dogs can get sick just like humans, so it’s your responsibility as a pet owner to ensure their well-being. Don’t hesitate to visit your nearest animal clinic if you notice any signs of illness in your dog

Dogs are not an exception to illnesses. As a pet owner, it’s your responsibility to look after their welfare. When your dog shows sickness symptoms, it is advisable to visit the nearest animal clinic. 

One comment on “How Do You Know a Dog Is Sick”

  1. Luke Smith

    It’s nice that you mentioned how changes in appetite would allow you to know if your dog is sick. I noticed that our dog wasn’t eating much lately and it is making me quite worried. I should probably bring him to a vet later for a checkup.

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