Get

In Your Inbox

Dogster is reader-supported. When you buy via links on our site, we may earn an affiliate commission at no cost to you. Learn more.

How to Tell if a Dog Has a Fever: Vet-Reviewed Tips & What to Do

medical treatment of sick husky dog in vet clinic

It’s heartbreaking to watch your pet endure a fever. Like humans, dogs experience a fever when their body temperature is higher than normal. A healthy dog should have a temperature of around 101–102.5°F, whereas a fevered dog may experience temperature fluctuations much higher than the norm.

In this article, we will review the signs of fever and some potential causes in dogs. We will also discuss how to take your dog’s temperature and soothe your poor pup. To learn more about caring for your fevered dog, keep reading below.

Disclaimer: If your dog is suffering from a fever or is unwell in any way, it’s important to speak to a vet promptly rather than to self-diagnose. There are many potential causes of fever, and all of them require veterinary attention, while some may be an indicator of a more serious health issue. The sooner your dog receives a diagnosis and appropriate treatment, the better their chances of recovery. The information in this article has been reviewed by a vet but cannot cover the vast multitude of causes of fever in dogs. This article is intended to provide useful information but is not a substitute for a thorough clinical examination performed by a veterinarian.

divider dog paws oct 2024

Signs of Fever

Other than an abnormally high body temperature, several signs may indicate that your dog is suffering from a fever. Some of the most common signs include:

  • Lethargy or weakness
  • Redness of the eyes
  • Warm ears and a warm, dry nose (not a reliable indicator)
  • Red gums
  • Lack of appetite
  • Breathing fast or panting
  • Shivering
  • Reluctance to move and walk
  • Discomfort

A dog’s body temperature may also change due to strenuous exercise, outside air temperature, and excessive excitement, but these fluctuations tend to be subtle and resolve themselves fairly quickly. Therefore, looking for these other signs is critical when trying to detect a fever. However, the best way to confirm whether or not your dog has a fever (as well as why they have one) is to take them to the vet. Depending on the root cause, cases of fever are accompanied by gastrointestinal signs, urinary issues, breathing changes, coughing, neck pain, limping, or others.

When to Take Your Dog to the Vet

When your dog’s temperature hits 103°F or higher, take them to the vet. Temperatures over 106°F can damage their organs, leading to fatal consequences. It is better to go early and be safe rather than sorry.

If you need immediate medical assistance, you can contact an online vet for help while you make your way to the nearest veterinarian.

Did you know you can speak to a veterinarian without having to travel? Just head over to PangoVet. It's an online service where you can talk to a vet online and get the advice you need for your pet — all at an affordable price!

PangoVet_Mention-in-Content Savings V1

divider dog paws oct 2024

The 7 Causes of Fever & Common Examples

There are several reasons why your dog may have a fever, and not all of them are clear-cut. But for the most part, canine fevers fall into one of these categories: inflammation, infection, immune-mediated, and cancer-related. Sometimes, the cause of a fever may be impossible to determine.

1. Vaccinations

Vaccinations are essential to your dog’s well-being, as they boost the immunity against diseases that may threaten their health. While they are vital to your dog’s long-term health, they can cause some minor short-term side effects. A fever is among them since anything that activates the immune system has the potential to lead to a fever. Other medications can also lead to adverse reactions and fever.

Other side effects may include:
  • Mild redness and swelling of the injection site
  • Fatigue
  • Decrease in appetite
  • Nasal discharge, coughing, or sneezing (in case of a kennel cough vaccine)
  • Anaphylaxis (rare)

The fever from vaccinations tends to be inconsequential and short and rarely ever requires veterinary treatment. Still, if your dog appears uncomfortable or the side effects last longer than 24 hours, reach out to a vet. On the other hand, anaphylaxis requires emergency veterinary attention and may manifest as swelling on the face, hives, breathing difficulties, vomiting, diarrhea, and others.

hand holding syringe for rabies vaccine with a black dog in the background
Image Credit: Numstocker, Shutterstock

2. Inflammatory Conditions

Inflammation is the body’s normal response to insult, such as trauma, injury, or irritation. Oftentimes, the cause may be difficult to pinpoint. Inflammation may occur without an infection. One of the most common inflammatory conditions in dogs is pancreatitis.

Pancreatitis is the inflammation of the pancreas, which is responsible for creating digestive enzymes used to break down food. This inflammation is due to an early activation of the digestive enzymes, causing the pancreas to digest itself. It manifests as lethargy, abdominal pain, vomiting, reduced appetite, diarrhea, weight loss, and in acute cases, collapse and even shock.

Another example of an inflammatory disease is a syndrome called Inflammatory bowel disease, which is a large group of conditions triggered by various factors, such as parasites, bacterial infections, and disbalance in the normal gut bacteria population, and it may also be immune-mediated.


3. Immune-Mediated Conditions

Autoimmune or immune-mediated diseases are closely linked to the immune system, and a flare-up may lead to a fever. Autoimmune diseases prevent your dog’s immune system from distinguishing between foreign bodies and the regular, healthy cells within your dog’s body. This causes the immune system to attack itself, causing damage to the body.

In some cases, the underlying cause may involve an infection, toxin, or even cancer that has stimulated the immune system into destroying its own cells. However, in many cases, the cause may remain unknown. Some breeds and age groups may be predisposed to certain immune-mediated conditions.

Some of the most common immune-mediated conditions in dogs are:
  • Immune-mediated hemolytic anemia – destruction of red blood cells, causing anemia
  • Immune-mediated thrombocytopenia – destruction of platelets, causing clotting issues
  • Immune-mediated polyarthritis – joint inflammation, causing pain and limping
  • Meningoencephalitis – inflammation of the brain and meninges, causing neck pain
Signs associated with immune-mediated conditions, alongside fever, greatly depend on the affected body system and may manifest as:
  • Reduced appetite
  • Lethargy and weakness
  • Collapse
  • Pale or jaundiced gums
  • Clotting issues, bruising
  • Blood in urine or feces
  • Limping
  • Joint pain and swelling
  • Stiff and painful neck
  • Vomiting
  • Diarrhea

The large variety of conditions and signs associated with immune-mediated illnesses shows how important it is to contact a vet if you suspect your dog has a fever. They will be able to diagnose if your dog is suffering from an immune-mediated or other condition.


4. Bacterial, Fungal, Protozoal, or Viral Infections

Infections of all sorts can lead to fever in your dog. Whether the infection is bacterial, fungal, protozoal, or viral, it can stimulate an immune response and lead to a fever. Protozoa are single-celled parasitic organisms that can be transmitted by tick bites and cause damage to the blood cells or be ingested, leading to gastrointestinal signs. Some of the causes of fever in dogs may include infections such as Leptospirosis, Brucellosis, Parvovirosis, and Distemper.

Signs of infection in dogs may vary depending on the specific culprit and affected organs or tissues. You can expect to see lethargy, sneezing, coughing, or other breathing problems if the respiratory tract is affected, or urinary issues if the kidneys or bladder are affected. Gastrointestinal infections (and parasite infestations) cause vomiting, reduced appetite, painful abdomen, and diarrhea. Infections of the skin and ears or wounds can also lead to fever, alongside redness and swelling, itching, and discharge from the skin or inside the ears.

dalmatian dog looking sick
Image Credit: Alexander Hagseth, Shutterstock

5. Sepsis

Sepsis may occur when the body is reacting to an infection. It is an extreme reaction that can lead to inflammation throughout the entire body and even cause organs to shut down. This condition can quickly become life-threatening.

Signs of acute pancreatitis include:
  • Lethargy
  • Vomiting
  • Diarrhea
  • Loss of appetite
  • Disorientation or confusion
  • Rapid heart rate or breathing
  • Low blood pressure

If you suspect that your dog has sepsis, contact a vet immediately; it is a medical emergency.

dog not eating its food
Image Credit: Daria Lixovetckay, Shutterstock

6. Ingestion of Toxins

Dogs seem to love to get into things they shouldn’t. At best, this causes a minor tummy ache. At worst, it can lead to a toxic reaction. There are several things dogs should never eat, including alcohol, chocolate, and onions. If your dog is experiencing a fever or has eaten something they shouldn’t have, immediately reach out to a vet or local emergency clinic. If possible, bring the label of the ingested item with you so that the vet can evaluate the severity of the problem.


7. Cancer

The most concerning diagnosis any dog may get is cancer. This is the word we are all dreading. There are many types of cancer in dogs; some are benign and can be resolved with surgery or even monitored by a vet, while others are malignant, requiring a combination of surgery and chemotherapy. Some cancers may be too far gone by the time a diagnosis is reached.

Cancer can cause cell and tissue destruction, which may in turn lead to fever. It can affect any tissue or organ system, including the skin, digestive, urinary, respiratory tract, bones, muscles, and others. The vet will be able to confirm which type of cancer it is by performing X-rays, scans, and biopsies, and will recommend the best treatment or management option for it.

divider dog paws 3 oct 2024

How to Soothe Your Dog’s Fever

To help your dog battle a fever, a vet will prescribe appropriate medication depending on the cause and may hospitalize your dog for intravenous fluids and painkillers. They will also instruct you on how to care for your dog when they’re ready to be discharged from the clinic and when they should come back for a check.

How to Take Your Dog’s Temperature

Taking your dog’s body temperature is the best way to detect a fever. Two instruments can be used to measure your dog’s internal temperature: a digital ear thermometer or a digital rectal thermometer. Older mercury thermometers are no longer considered safe or appropriate for usage.

Ear thermometers are the least invasive (and probably less daunting) of the two options. You will gently insert the ear thermometer into your dog’s horizontal ear canal.  However, if not inserted properly, which can be tricky and will depend on the length of the ear canal and the dog’s tolerance, the measurement may be inaccurate.

Rectal thermometers are considered the gold standard for measuring a dog’s temperature, though many people may find them less appealing for obvious reasons. If you use a rectal thermometer, lubricate it with baby oil or petroleum jelly. Wait until the thermometer beeps for an accurate reading.

No matter which thermometer you choose to use, make sure that you follow the instructions carefully, to avoid injuring your dog or getting an incorrect reading.

Image Credit: Krysja, Shutterstock

divider single dog paw oct 2024

Conclusion

No one likes to see their dog suffer from a fever. Regardless of the cause of the fever, watching our pets endure sickness is a difficult matter. We hope this article has helped you spot the signs of fever and learn more about the potential causes. If you believe your dog is battling a fever, do not delay getting them the veterinary treatment they need. The sooner they are healed, the sooner they can return to their tail-wagging self!

Related reads:


Featured Image Credit: Pressmaster, Shutterstock

How useful was this post?

Click on a star to rate (you can leave written feedback after clicking submit)

Help us improve Dogster for pet parents!

Your feedback really matters.

What did you like about this post? Also how can we improve it?

Join the conversation

Leave a Reply

You’re very welcome to leave a comment or question. Please know that all comments must meet our community guidelines, and your email address will NOT be published. Let’s have a positive and constructive conversation.

Talk With A Vet Online

Peace of mind,
anywhere, anytime

Affordable vet advice

140 Dog Names Starting With R for a Remarkable Pup

If you have just adopted a new dog into your family and are looking for great name ideas, you have come to the...

Are Dogs Allowed in Target? 2025 Update

Our furry friends are more than just pets, they are family. So, of course, we want to bring them everywhere with us. You’ve...

Nutra-Nuggets Dog Food Review 2025: Pros, Cons & Recalls

Review Summary Nutra-Nuggets is a pet food company that’s under the umbrella of Diamond Pet Foods. It has two main lines of food—US...

Cost to Spay or Neuter a Dog In Australia: 2025 Price Guide

No matter where you live, the decision to spay or neuter your dog isn’t an easy one. Desexing surgery is marginally more expensive...

More related

Fo Tzu (Toy Fox Terrier & Shih Tzu Mix): Info, Pictures, Care & More

When many people think of the stereotypical lapdog, they picture a high-maintenance animal that expects to be treated like royalty and isn’t afraid...

Do Rottweilers Shed? Reasons & Way to Help

With their sturdy bodies and blocky heads, Rottweilers are one of the most recognizable and popular dog breeds out there. Equally at home...

7 Best Lick Mats for Dogs in 2025: Reviews & Top Picks 

Licking is a soothing behavior for dogs.1 Lick mats are special toys with patterned nubs that you fill with a spreadable treat, such...

11 Best Dog Foods for Basset Hounds in 2025 – Reviews & Top Picks

What’s not to love about those droopy eyes and long, floppy ears? Basset Hounds have a way of digging themselves into your heart,...

Keep reading

Is Lamb Dog Food Good for Dogs? Vet-Reviewed Benefits & FAQ

There are a host of dog foods out there to choose from when it comes to feeding your dog and many different meat options available to tempt your pet’s palate. While a good majority of dog foods will contain chicken,...

dachshund dog eating from elevated bowl

How to Make Dog Treats to Sell at Home & Start a Business: 11 Tips

If there’s one thing we know about dogs, it’s that they absolutely love having as much food to eat as possible. It seems most dogs are willing to stuff just about anything in their gullet. So, you could make some...

Bone and paw-shaped dog treats on cookie sheet

Raw Dog Food Diet Plan: Vet-Approved Guide to Get Started

Raw food diets for dogs are surrounded by controversy, but they’re becoming more popular among dog owners. These diets aren’t new. Racing Greyhounds and sled dogs have been eating raw diets for decades, and an Australian veterinarian, Ian Billinghurst, proposed...

Husky wolf dog excited to be fed with raw food

8 Best Dog Foods for American Bullies in 2025 – Reviews & Top Picks

American Bullies are a new breed with old roots. They’re closely related to Pit Bull Terriers and Bulldogs, and their strong, muscular forms require a lot of fuel. When you’re looking for food to keep your Bully going, look for...

American Bully eating

Can Dogs Eat Dill? Vet-Verified Nutrition Facts & Preparation Ideas

Dill (Anethum graveolena) is a member of the parsley family, Apiaceae, and is safe to feed to dogs, in moderation. There is no evidence that indicates that dill causes problems in dogs, but it is always best to feed it...

Dogster-Can-Dogs-Eat-Dill

Can Dogs Eat Flaxseed? Vet Reviewed Diet & Health Facts

Flaxseeds, sometimes known as linseeds, provide a host of nutritional benefits to humans. They are packed with essential omega-3 and omega-6 fatty acids and have anti-inflammatory properties that can ease joint pain and arthritis. But can dogs have flaxseed? The...

Can Dogs Eat_Flaxseed

Can Dogs Eat Salmon Skin? Vet-Approved Facts & FAQ

If you pay attention to dog food labels, you might know that salmon is a common protein source, especially in limited-ingredient diets. Knowing this, you can assume that salmon is safe for dogs to eat, but what about the skin...

Can Dogs Eat Salmon Skin

How Long Will It Take for a Dog to Digest a Bone? Vet-Verified Facts & Risks

Dogs and bones seem like a match made in heaven, but should you be worried if your dog swallows a bone? And can dogs digest a bone if they do eat one? The answer is pretty complicated. Dogs can digest...

red border collie dog chewing on a bone