Hepatitis in dogs, or inflammation of the liver, can occur for many reasons. Integrative veterinarian Dr. Julie Buzby discusses the types, causes, symptoms, diagnosis, and treatment for hepatitis in dogs so you will know what to expect should your dog be facing this diagnosis.
If you’ve ever noticed a medical word ending in “-itis,” here’s a little secret—it’s doctor-speak for “inflammation.” So, when you hear the term hepatitis in dogs, it simply means your pup has inflammation of the liver.
Now, why might a diagnosis of hepatitis be a cause for concern? Imagine your pup’s liver as a busy airport hub. Planes (nutrients and chemicals) constantly land and take off, passengers (toxins) get screened, and cargo (energy and vitamins) gets sorted and stored for later flights. The liver keeps everything moving safely and efficiently.
When these “airport” processes break down, flights get delayed, passengers pile up, and important cargo can’t get where it needs to go. In other words, when hepatitis stops the liver from functioning appropriately, it can impact your dog’s whole body.
What is hepatitis in dogs?
Hepatitis means there’s inflammation in the liver, but why that inflammation is happening can vary widely. It’s important to understand that hepatitis isn’t a single, specific disease—it’s more like an umbrella term. In dogs, infections (like certain viruses or bacteria), toxins, an overactive immune system, or even other underlying health issues can all cause hepatitis.
So, when your veterinarian mentions they are concerned about hepatitis, this is just the beginning. The next step is to figure out what’s causing the liver inflammation in the first place. This is important because treatment and outlook can be very different depending on the root cause.
When talking about hepatitis in dogs, you might also hear your veterinarian use words like acute or chronic. These simply describe how long the liver inflammation has been present.
Acute hepatitis in dogs
Acute hepatitis means the liver has become inflamed suddenly. This can happen over hours or days, usually due to infections such as infectious canine hepatitis, certain toxins, or reactions to some medications.
Dogs with acute hepatitis may suddenly seem very sick. They might stop eating, vomit, have a yellow tint to their eyes or gums (jaundice), or act very tired. The good news is that if caught early, acute hepatitis can often be reversed with the right treatment and supportive care.
Chronic hepatitis in dogs
Chronic hepatitis, on the other hand, means the inflammation has been going on for a long time. It can develop over the course of weeks, months, or even years. Sometimes it starts mild and slowly damages the liver over time until the liver fails. The symptoms tend to be more subtle, and unfortunately, chronic hepatitis cannot be cured, only managed.
We will cover chronic hepatitis is more detail later in this article but for now, keep in mind that understanding whether your dog’s hepatitis is acute or chronic can help your veterinarian decide which tests and treatments are best.
Infectious canine hepatitis—A cause of acute hepatitis in dogs
One specific cause of acute hepatitis in dogs is a viral disease called infectious canine hepatitis. While it’s quite rare today thanks to vaccines, it is both important and different enough from the other causes of acute hepatitis to be broken out on its own.
Infectious canine hepatitis (ICH) is caused by a virus called canine adenovirus type 1 (CAV-1). Puppies and young dogs who are unvaccinated are most at risk because they don’t yet have immunity against the virus. Dogs usually get infected by coming into contact with the body fluids (urine, saliva, or feces) of another infected dog. However, wild animals like foxes, coyotes, and wolves can also catch and spread ICH.
CAV-1 enters the dog’s body most often through the nose or mouth. For example, dogs can become infected when sniffing or licking something contaminated like a shared water bowl, grass, or even toys.
Once inside the body, the virus multiplies in the tissues of the tonsils and lymph nodes. From there, it spreads through the bloodstream to major organs, especially the liver, but also the kidneys, eyes, and the lining of blood vessels.
What are the symptoms of infectious canine hepatitis?
After exposure to canine adenovirus type 1, signs won’t be noticeable right away. This “waiting period” before symptoms show up is called the incubation period. For infectious canine hepatitis, it’s usually about four to nine days.
Once symptoms begin, they can range from mild to severe, and can include:
- Fever—Your dog may feel warm to the touch, and if you take your dog’s temperature, it will be above 102.5oF
- Watery discharge from eyes and nose—Some dogs with ICH have ocular or nasal discharge
- Lack of appetite—Dogs who are sick with ICH may not feel up to eating
- Being a lethargic dog—The dog may lay around or sleep more than normal
- Vomiting and diarrhea—Dogs with hepatitis may be nauseous, vomit, or have diarrhea.
- Abdominal pain—A dog with belly pain might be hunched over or in a play bow position.
- Jaundice—The dog may have a yellow tint to the gums, eyes, or skin.
- Corneal clouding— The virus can cause a cloudy, bluish appearance in one or both eyes due to inflammation in the cornea. This finding is sometimes called “blue eye”.
- Bleeding problems—Because the liver helps produce clotting factors, dogs with severe cases of ICH may have signs of bleeding such as a bruised or reddened nose or mouth, bruising on the skin, or tiny red spots (called petechiae) on the gums.
Some dogs, especially puppies, can rapidly become extremely sick. If you see any combination of these signs—especially jaundice or sudden severe illness—the most important thing to do is to contact your veterinarian right away.
How is infectious canine hepatitis diagnosed?
Diagnosing ICH usually starts with your veterinarian putting together the whole picture—your dog’s symptoms, age, vaccination history, and possible exposure to other dogs or wildlife.
Because the signs of ICH can look like other diseases such as canine distemper or leptospirosis, your veterinarian may run blood tests for dogs to check for liver damage and problems with clotting. Then, if your veterinarian remains concerned about ICH, he or she can submit special tests like PCR (a lab test that detects the virus’s genetic material) or antibody tests to help confirm the diagnosis.
What is the treatment for infectious canine hepatitis?
There’s no specific cure for infectious canine hepatitis, so treatment focuses on supportive care. This usually means keeping infected dogs well-hydrated with fluids, controlling vomiting, keeping them out of bright light if they have eye inflammation, and providing good nutrition. Some dogs may also need a blood transfusion due to abnormal clotting and/or broad spectrum antibiotics to reduce the risk of secondary infections.
Dogs with mild cases of infectious hepatitis may recover at home with close monitoring and vet guidance. But more severe cases often need to stay in the hospital for intensive care.
What is the outlook for dogs with infectious canine hepatitis?
With early diagnosis and good supportive care, many dogs can recover from ICH. However, recovery time can vary, and some dogs have lingering liver damage. Due to immune complex reactions (combinations of the virus and immune-system proteins that may lodge in tissues), dogs may also have kidney damage or permanent changes to their eyes. And even after dogs recover, they can shed the virus in their urine for up to to nine months.
This all sounds quite grim, but the great news is that we have a safe and effective way to prevent infectious canine hepatitis.
How can you prevent infectious canine hepatitis?
The best way to protect your dog from ICH is through vaccination. The vaccine for ICH is usually included in the routine “canine distemper vaccination” or “DHPP”. These combination shots typically cover distemper, hepatitis, parvovirus, and parainfluenza.
Puppies get a series of these shots starting at around six to eight weeks old, with boosters every few weeks until they’re about 16 weeks old. After that, adult dogs get regular booster shots to keep their immunity strong.
Taking steps to prevent exposure to the virus helps too. It is a good idea to avoid letting your dear dog drink from shared water bowls or sniff areas where lots of dogs gather, especially if you’re unsure about their vaccination status.
Other causes of acute hepatitis in dogs
While infectious canine hepatitis is a well-known cause of acute hepatitis, there are several other reasons for sudden liver inflammation in dogs. Here are the most common:
1. Toxins
Dogs are naturally curious, and unfortunately, many everyday items can be harmful to the liver. Some toxins that can cause acute hepatitis include:
- Xylitol (birch sugar) toxicity—This sugar substitute found in products like gum and baked goods is safe for humans but toxic to dogs.
- Certain mushrooms—Amanita phalloides (death cap mushroom) is the main mushroom to cause acute liver inflammation, but mushrooms in the genera Amanita, Galerina, and Lepiota can be toxic to the liver too.
- Blue-green algae toxicity in dogs—Blue-green algae grows especially well in stagnant water and can cause rapid death.
- Aflatoxin poisoning in dogs—Aflatoxins are produced by a fungus (Aspergillus) that sometimes grows on pet food ingredients or moldy or poorly-stored kibble.
However, keep in mind that this is not an exhaustive list of toxins that target the liver.
2. Medication reactions
Some medications—even those prescribed by a veterinarian—can occasionally trigger liver inflammation. Common culprits include certain antibiotics, anti-seizure medications, or non-steroidal anti-inflammatory (NSAID) pain relievers (especially if given at the wrong dose or for too long).
3. Bacterial infections like leptospirosis
Leptospirosis is a bacterium that is spread through contaminated water or urine and can affect the liver and kidneys. The good news is that Lepto is treatable with antibiotics. And the even better news is that there are effective vaccines available to help prevent your dog from contracting Lepto in the first place.
Leptospirosis is not the only bacterial culprit, though. Sometimes other bacterial infections can spread from the gallbladder into the liver. Once there, they cause a condition known as cholangiohepatitis. This mouthful of a term just means there is inflammation of both the gallbladder and the liver.
4. Unknown (idiopathic) acute hepatitis
In some cases, despite the vet’s best efforts, it isn’t possible to find a clear cause for the acute hepatitis. These are called idiopathic cases. Even without a known trigger, the vet must still manage the inflammation to protect the liver.
What does acute hepatitis look like in dogs?
The signs of acute hepatitis in dogs can vary depending on the cause and how severely the liver is affected. But they often appear suddenly and mimic the signs of infectious canine hepatitis listed above (vomiting, diarrhea, lethargy, poor appetite, bleeding problems, abdominal pain, and/or jaundice). This makes sense since ICH is a form of acute hepatitis. One notable exception to this overlap is “blue eye” which is specific to infectious canine hepatitis.
How will the vet diagnose a dog with acute hepatitis?
When your veterinarian suspects acute hepatitis, he or she will take a thorough history and perform a complete physical exam. Then he or she will recommend a series of tests to evaluate liver function and look for possible causes.
A typical diagnostic workup might include:
- Bloodwork (CBC and chemistry panel) and a urinalysis—A chemistry panel checks liver enzyme levels, bilirubin, and levels of the products made by the liver (albumin, cholesterol, and glucose). The CBC provides white blood cell, red blood cell, and platelet counts. To assess kidney function and look for bilirubin in the urine, the veterinarian may run a urinalysis.
- Abdominal ultrasound—This non-invasive imaging modality gives more detailed information than X-rays. It allows your veterinarian to visualize the liver and look for abnormalities like swelling or masses. An inflamed liver may also appear brighter than normal on ultrasound.
- Infectious disease testing—The vet may run leptospirosis titers or PCR testing, especially if the vet suspects an infection
- Liver function tests—Bile acid testing or assessing the levels of ammonia in the blood can help provide additional information about the liver.
Your precious pup’s unique history, exam findings, and diagnostic results act like puzzle pieces to help your veterinarian find the most likely cause and create a treatment plan.
What is the treatment for acute hepatitis in dogs?
Treatment for acute hepatitis focuses on supporting the liver while addressing the underlying cause (if found). In most cases, dogs suffering from acute hepatitis need supportive care such as IV fluids to prevent dehydration, anti-nausea medications, and liver-protective supplements like SAMe or silymarin (milk thistle).
If the vet is suspicious of a toxin or drug reaction, it is important to remove the source immediately. Plus the vet may administer treatments to help the liver process the harmful substance.
In the case of an infection, antibiotics will be part of the treatment regimen too.
What is the outlook for acute hepatitis in dogs?
Many dogs with acute hepatitis recover well with prompt treatment, especially if the liver hasn’t suffered extensive damage. The goal is to give the liver time and support to heal. Thankfully, the liver is one of the few organs that can regenerate, which helps many dogs bounce back beautifully.
Plenty of dogs who survive acute hepatitis go on to live normal lives. But others need long-term monitoring or liver support. In a few cases, what begins as acute hepatitis can slowly evolve into chronic hepatitis, especially if the underlying issue isn’t completely resolved.
That brings us to the next important topic—chronic hepatitis in dogs.
What is chronic hepatitis in dogs?
Chronic hepatitis is long-term inflammation of the liver that develops slowly over time. As the liver sustains continued damage, it eventually becomes scarred (a process called fibrosis).
This scarring begins to interfere with the liver’s ability to do its many jobs like filtering toxins, processing nutrients, and making factors that are required to help the blood clot. If the inflammation is both significant and persistent, then the ongoing damage to the liver can eventually lead to liver failure in dogs.
What are the symptoms of chronic hepatitis in dogs?
Chronic hepatitis can be tricky to spot early in the disease because many dogs don’t show obvious symptoms at first. Sometimes by the time signs appear, the liver has sustained a critical amount of damage, making it hard for the dog to recover.
Some potential signs of chronic hepatitis in dogs include:
- Weight loss—Despite not changing your dog’s diet or exercise levels, you might notice your dog looks thinner or his or her ribs are more prominent.
- Low energy—Dogs with chronic liver failure may not feel like being as active as before. They may lie around more or tire out easily with activity.
- Vomiting—GI upset can sometimes accompany liver failure, especially as toxins build up.
- Jaundice—Since the liver isn’t excreting bilirubin (a yellowish orange pigment) as well, it builds up in the body, leading to yellowing of the skin, gums, and eyes.
There are a few common causes of chronic hepatitis, which we’ll explore next. But it’s also important to know that sometimes the vet never finds the exact trigger. Regardless of the cause, early detection and long-term management are key to slowing down the disease and helping your dog live a longer, more comfortable life.
What are the common causes of chronic hepatitis in dogs?
Several different conditions or situations can cause chronic hepatitis in dogs. Each of the known causes differ somewhat in how your veterinarian might approach diagnosis and treatment.
However, for all the causes of chronic hepatitis, you can increase the chances of a positive outcome by bringing your pup for regular visits to your veterinarian. This allows him or her to monitor liver values and discuss any necessary adjustment to the treatment plan.
Some of the most common causes of chronic hepatitis in dogs include:
Copper hepatopathy in dogs
Copper hepatopathy results from a dog’s body storing too much copper in the liver. Dogs do need small amounts of copper for healthy metabolism. But too much copper is toxic to the cells of the liver. There are two main ways dogs can develop copper hepatopathy:
1. Genetic (inherited) copper buildup
Some dogs are born with a genetic tendency to absorb and store too much copper in their livers. Over time, the copper accumulates to dangerous levels.
Breeds at higher risk include:
- Bedlington Terriers
- Labrador Retrievers
- Doberman Pinschers
- Dalmatians
- West Highland White Terriers
- Cocker Spaniels
- Skye Terriers
2. Dietary or secondary copper accumulation
In other dogs, copper builds up secondarily (because of another problem). It can be due to a liver issue like inflammation that blocks normal copper excretion or from eating a diet that is too high in copper.
Reaching a diagnosis of copper hepatopathy
Regardless of the cause, the vet can’t diagnose copper hepatopathy based on bloodwork alone. High liver enzymes in dogs are common in affected dogs, but reaching a definitive diagnosis requires a liver biopsy.
This involves surgically removing a small portion of the liver and sending to the lab for analysis. At the lab, the pathologists examine the samples under a microscope and measure the copper content. This helps confirm the presence of hepatitis and determine whether copper accumulation is the driving factor.
Treating copper hepatopathy in dogs
Treatment for copper hepatopathy focuses on reducing the amount of copper in the liver and controlling inflammation. This usually includes copper-restricted prescription liver diets. Plus, the dog may need chelation therapy with medications like D-penicillamine that help remove copper from the body.
Other supportive treatments include liver-protective supplements and sometimes anti-inflammatory doses of steroids. Affected dogs often need lifelong management, especially if they are genetically predisposed to copper accumulation.
Prognosis for copper hepatopathy
The good news is that if copper hepatopathy is caught early and managed properly, many dogs can maintain a good quality of life for years. On the other hand, if the disease is advanced or left untreated, it can lead to irreversible liver damage or failure.
Immune-mediated hepatitis in dogs
If your dog has immune-mediated hepatitis, their immune system is mistakenly attacking their own liver cells, treating them as if they were a threat like a virus or bacteria. This misguided immune response leads to ongoing inflammation, which damages liver tissue over time. If not treated, this inflammation causes scarring (fibrosis), cirrhosis, and eventually liver failure.
The exact cause of immune-mediated hepatitis is not always clear. It may be triggered by a combination of genetics (certain breeds can be predisposed), environmental factors, and/or previous infections or drug exposures that have “confused” the immune system. In many cases the immune system simply goes rogue without an obvious outside trigger.
Breeds that may be more at risk for immune mediated hepatitis include Doberman Pinschers (especially females), Standard Poodles, Cocker Spaniels, and Labrador Retrievers. However, it can affect any breed of dog.
Diagnosing immune-mediated hepatitis
The process for diagnosing immune-mediated hepatitis tends to be quite similar to that used for acute hepatitis. It usually involves blood tests to check liver enzymes and liver function, and to rule out infections. Plus the vet may use imaging like ultrasound to assess the size and shape of the liver.
Where the diagnostic work-up differs, however, is in the fact that liver biopsies are part of the definitive diagnosis for all causes of chronic hepatitis. In the case of immune mediated hepatitis, these biopsies would show inflammation and help rule out other causes of chronic hepatitis like excessive copper buildup.
Treatment for immune-mediated hepatitis
Medications to suppress the immune system are the main treatment for immune-mediated hepatitis. This usually means putting the dog on high doses of corticosteroids like prednisone for dogs. But treatment also could include secondary immunosuppressive medications like cyclosporine or mycophenolate. The goal of therapy is to tamp down the immune system so that it stops attacking the liver.
Prescription liver diets and adjunctive liver supplements may also be a part of the treatment plan.
Outlook for dogs with immune-mediated hepatitis
Like with copper hepatopathy, many dogs with immune-mediated hepatitis can live happy lives for years with early diagnosis and proper treatment. However, immune-mediated hepatitis is a lifelong condition that often requires long-term medication and monitoring.
Chronic infections as a cause of chronic hepatitis in dogs
Some bacterial, viral, or fungal infections can settle in the liver and cause low-grade, persistent inflammation over time. These are less common than other causes but still important to rule out. Reaching a diagnosis starts with lab work and imaging. But then it may progress to more specific testing for infections in addition to liver biopsies.
Chronic hepatitis in dogs due to drug or toxin exposure
Certain medications or repeated exposure to toxins can cause liver damage over time. Even if the exposure doesn’t cause a sudden reaction, the liver may quietly accumulate damage, eventually leading to chronic inflammation. However, this too is a less common cause of chronic hepatitis.
If your veterinarian suspects an issue with your dog’s liver, he or she can talk you through a list of medications or toxins that have the potential to be toxic to the liver. Stopping the offending medication or preventing further toxin exposure, in combination with supportive care, can increase the likelihood of recovery.
Unknown (idiopathic) chronic hepatitis in dogs
Unfortunately, in many cases of chronic hepatitis, we never find a clear cause even with a thorough diagnostic work-up. In other words, it is idiopathic.
Even without a known trigger, it is important to manage the liver inflammation to prevent further damage. The vet may use liver-protecting medications, general supportive care, and sometimes anti-inflammatory doses of steroids to treat chronic hepatitis when the inciting cause is unknown.
Your vet can help you navigate a hepatitis diagnosis
Facing a suspected diagnosis of liver disease in your dog can feel overwhelming. But understanding the different forms can help pet parents like you feel more informed and empowered. No matter the cause, hepatitis signals a disruption at one of the body’s busiest hubs—the liver.
Whether it’s a sudden storm like acute hepatitis, brought on by an infection or toxin, or a slow and steady build-up like chronic hepatitis caused by copper accumulation or an overzealous immune system, the result is the same—the liver, your dog’s metabolic airport, starts to struggle.
And just like a real airport in chaos, the effects ripple through the entire system. But here’s the hopeful part. The liver is one of the few organs with an incredible capacity to regenerate. With the right support, all those vital processes can get back on track. That’s why early recognition, accurate diagnosis, and ongoing care are so important.
And don’t forget, you’re not navigating this flight path alone. Your veterinarian is your trusted co-pilot, helping you interpret lab results, tailor treatments, and make informed decisions that fit your dog’s unique needs. Together, you can help keep your pup’s internal airport running as smoothly and safely as possible—ensuring many more joyful takeoffs and tail-wagging landings ahead.
Has your dog ever had hepatitis?
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