As a pet owner, hearing the word “tumor” come out your vet’s mouth is a nightmare.

The sheer sound of the word tumor immediately creates all kinds of negative thoughts.

However they aren’t all bad.

In fact, many are benign, meaning they won’t spread or affect your dog negatively.

And even those that do can often be treated or managed (at least for some time) using special treatments and medicines.

One of those medicines which can treat tumors is CBD, an all-natural compound found in cannabis and hemp plants.

If you have a dog suffering with tumors, I’ll explore how CBD can potentially help.

I’ll also share some unique details about my experience with using CBD on my Golden Retriever, Rosie.

Our Pick:

HolistaPet CBD Tincture

One brand I love to recommend for more serious ailments is HolistaPet. Their oils have amazing ingredients and get great customer reviews.

View their official website here

Exclusive Bonus: Download a free checklist and find out if CBD is right for your dog. Plus get a report (35 pg PDF) on CBD for dogs. Get your copy here.

What are Tumors?

Dog tumors are no different to the tumors affecting humans.

In its most basic sense, a tumor is an unusual lump caused by the abnormal growth of cells.

These cells grow abnormally to form a swelling which we then refer to as a tumor.

Tumors can be malignant or benign.

What Kinds of Tumors Affect Dogs?

Dogs, just like humans, can develop a wide variety of tumors.

Below I’ll outline some of the most common types of tumors affecting dogs.

  • Mast cell tumors: Mast cells tumors affect a specific type of blood cell. They form in the skin and are one of the most common types of skin tumors affecting canines. They generally grow very fast and are usually very red and itchy as they contain histamine. Short-faced dog breeds like Boxers, Pugs, and French Bulldogs are most at-risk of developing these tumors.
  • Lipomas: Lipomas are very common in dogs. They usually form under the skin and are caused by the abnormal growth of fatty tissue. Luckily, lipomas are slow growing and usually harmless. They can usually be detected easily as they form as soft, movable lumps under your pet’s skin. Once they’ve been correctly identified, lipomas are usually left alone unless they impede a dog’s movement or activity.
  • Osteosarcoma: Osteosarcoma is a type of bone cancer affecting a specific type of cell that forms new bones. These tumors tend to affect the bones of the legs, but can also form elsewhere. They tend to affect giant dog breeds like Great Danes and Greyhounds, but also affect other breeds, too. The most common sign of osteosarcoma is limping.
  • Histiocytoma: This tumor affects skin cells known as histiocytes (which actually form part of the immune system). They tend to affect younger dogs (usually under 3 years of age), and usually to affect breeds like the English Bulldog, Scottish Terriers, Boxers, and Chinese Shar-Peis. Histiocytomas are typically benign and tend to regress on their own in just a few months. Some tumors may be removed surgically if they are particularly bothersome for a pet.
  • Hemangiosarcoma: These tumors affect cells in the lining of blood vessels. They almost exclusively occur in dogs and are particularly invasive. They usually develop on the spleen, which has a large blood supply, but may also form in vessels in the heart or skin. Hemangiosarcomas can cause the spleen to rupture, causing pale gums, difficulty breathing, and difficulty getting up. These tumors tend to spread to other parts of the body and are more common in Golden Retrievers and German Shepherds.
  • Melanoma: Melanoma (often just called “skin cancer”) affects pigmented skin cells. Like in humans, these tumors are usually visible on the skin as they form black or dark brown moles. Luckily, melanomas can be benign, although those forming in the mouth and nail bed tend to be particularly aggressive.
  • Lymphoma: These tumors form in the lymph nodes, causing them to swell. This can cause a variety of symptoms, including lethargy, loss of appetite, and coughing. Lymph node swelling is most noticeable under the jaw, in front of the shoulders, and behind the knees. These tumors are usually malignant and are generally treated with chemotherapy.
  • Papilloma: These tumors form as hard, cauliflower like warts on a dog’s lips, mouth, and around the eyes. They can be problematic for dogs as they can be painful and get infected. These tumors will usually develop then disappear within a few months, but they may also be removed surgically if they cause any problems for the dog. Luckily, they are benign.

Note that this list isn’t complete. These are just some of the most common tumors affecting dogs.

What Symptoms do Tumors Produce?

dog looking straight ahead

The symptoms your dog displays will vary depending on the type of tumor he/she has.

Some tumors, like melanomas, papillomas, and lipomas will cause noticeable growths that you or your vet will likely spot while inspecting your dog more closely.

Lymphomas, on the other hand, may produce no notable symptoms other than swelling, which can be harder to diagnose.

When affecting the gastrointestinal tract, however, lymphoma can cause vomiting, diarrhea, weight loss, and a lack of appetite.

The symptoms of hemangiosarcoma can vary depending on whether the tumor is visceral or dermal.

Some common symptoms of malignant tumors can include:

  • Limping (especially due to bone tumors)
  • Pain
  • Loss of appetite
  • Vomiting and nausea
  • Diarrhea
  • Sores that don’t heal
  • Lethargy
  • Loss of interest in exercise
  • Stiffness
  • Difficulty breathing and/or coughing

However, keep in mind that some tumors do not cause any symptoms, too.

How are Dog Tumors Treated?

Tumors first need to be diagnosed properly before your vet prepares a treatment plan.

To diagnose a tumor, vets will usually use one of more of the following diagnostics:

  • Lab tests (blood, urinalysis, etc)
  • X-rays and ultrasounds
  • CT scans or MRIs
  • Fine needle aspirate and fluid analysis
  • Biopsy

Once the vet has correctly diagnosed the type of tumor affecting your dog, they’ll usually begin making a treatment plan specifically for them.

If the tumor is benign and doesn’t cause any major discomfort to the dog, your vet will usually opt to leave it be.

If not, the next step is usually surgery to remove the tumor, part of it, or amputate the affected area.

Following surgery, your vet will usually recommend chemotherapy to minimize the growth or spread of the tumor in the future.

Can CBD Help Treat Tumors?

A few years ago, I received the news all pet owners dread most:

My dog Rosie was diagnosed with hip dysplasia and cancer.

Obviously, I was devastated.

Blake and Rosie up closeBut, determined to make her remaining years as enjoyable possible, I quickly began to look for ways to help support her treatment and her overall quality of life.

So, it wasn’t long before I stumbled on CBD.

While I was skeptical at first, I quickly learned about the huge potential of this tiny molecule.

And, once I learned it was completely safe to use on humans and animals, I decided to give it a shot.

And I’m so glad I did.

CBD almost immediately improved Rosie’s condition, helping her deal with the subtle side effects of chemo, while also reducing the pain and inflammation caused by the hip dysplasia.

As I dove deeper into the world of CBD, I soon learned that there was a strong body of evidence showing this compound can help both humans and pets deal with malignant tumors.

It does so in 2 main ways:

  • First of all, CBD can help your pet deal with the symptoms associated with cancerous tumors as well as the side effects of chemotherapy and other types of treatment.
  • Secondly, and arguably more importantly, CBD has been shown to help slow the growth and spread of a malignant tumors.

Here’s how:

How CBD Helps Treat Symptoms of Tumors

Some common symptoms of a malignant tumor in dogs include vomiting/nausea, lack of appetite, pain, and lethargy.

Research shows that CBD can help dogs deal with many of these symptoms.

For example, CBD is renowned as an antiemetic, helping dogs deal with symptoms like nausea and vomiting (generally caused by the tumor or chemotherapy).

That’s because the endocannabinoid system (the system responsible for mediating the effects of endo and phytocannabinoids) is involved in many biological processes, including appetite and metabolism.

In fact, research shows that the endocannabinoid system is heavily involved in the mediation of nausea and vomiting.

The system is predominantly made up of 2 receptors (CB1 and CB2).

These receptors are located all throughout the brain and body, including in the gastrointestinal tract.

By stimulating CB receptors in the brain and the GI tract, CBD has been shown to help reduce nausea and vomiting.

Research suggests it does so by binding to a specific type of receptor in the brain (known as 5-HT1A).

two labradors sitting down in a fieldBy helping reduce nausea and vomiting, CBD can also help dogs regain their appetite, which is often reduced when undergoing chemotherapy.

Other research also shows that CBD can help reduce the pain associated with some types of malignant tumors.

In fact, pain-relief is a very well-documented effect of CBD:

It does so by helping reduce inflammation as well as temporarily blocking pain signals sent to the brain.

Research also suggests that CBD can help pets deal with other symptoms/side effects of malignant tumors and their treatment (like chemotherapy).

CBD Can Slow Tumor Growth and Reduce Spreading

There is a solid body of research that shows CBD (and other components of cannabis and hemp) can help slow tumor growth and metastasis.

One of the main ways in which CBD does this is by impeding angiogenesis in tumors.

Angiogenesis is the process of forming new blood vessels.

Malignant tumors are able to produce their own blood vessels to bring more blood to the site and keep cells alive.

CBD has been shown to inhibit this process in a variety of ways.

Meanwhile, other studies also show that CBD can help slow the proliferation of cells in tumors, too.

I’ve covered the antitumor/anticancer effects of CBB in a previous articles.

For more information, check out this post on CBD for dogs with cancer.

Using CBD on Your Dog

Most pet owners are nervous about starting their pets on CBD.

And I get why.

However, you can rest assured that CBD is completely safe to be used on your furry friend.

In fact, CBD is completely non-toxic and incapable of producing an “overdose.”

And no, CBD won’t make your dog “high.”

The compound in marijuana that causes the iconic high we associate with “pot” is THC (or tetrahydrocannabinol).

CBD is another compound altogether.

Here are some tips to help you administer CBD to your pet:

Find the Right Dosage

When giving your dog CBD oil, always stick with the recommended dosage on the product itself.

When using CBD capsules or treats, the dosage will depend on the strength of the product you’re using.

For these products, it's always best to follow the package instructions that came with the product.

Remember that there are also topical CBD products for pets like sprays and balms.

These may be beneficial in treating tumors on the skin, such as mall stem tumors, for example.

When using topicals, I suggest applying them once per day, assessing how your dog responds, and then adjusting the dosage as necessary.

Overall, the dosage will really be associated with the brand of CBD you use. I discuss this in detail on the dosage guidelines page found here.

Read the Reviews From Other Pet Owners Just Like You

I mentioned earlier that I had great success using CBD on my dog Rosie.

But I’m not alone.

There are thousands of other pet owners all around the globe that give their pets CBD either as a medicine or health supplement.

These people have great results with CBD, and find it helps their pets deal with everything from eating problems to pain and anxiety.

Many of these people also use CBD to help their pets deal with malignant tumors or the side effects of treatment.

I wanted to quickly highlight a few testimonials that you might be able to relate to:

First we have Francesca.

Golden Retriever gives testimonial on CBD product
Screenshot taken from

Francesca is suffering from cancer and is undergoing treatments.

As many pet owners report, she seemed to be unhappy and tired from the typical treatments. So her owners started her on CBD and they've noticed that her energy levels are back up, and she seems much more happier now.

Next we have a testimonial from Robin.

pet cbd testimonial about tumors
Screenshot taken from

Robin wrote in to report the amazing news that CBD has had on her dog's cancerous tumor.

There was a very large tumor around the rib area which seemed to be stretching the dog's stomach. They started using CBD oil and have clearly noticed the tumor shrinking ever since.

There has been a clear drop in the inflammation surrounding the tumor, and they're super happy with the results so far.

Lastly, we have Rascal.

Rascal the dobermann giving a cbd review
Screenshot taken from

Rascal was suffering from a tumor in his heart which was causing a lot of problems such as fluid buildup in his lungs.

He had issues with his breathing, lack of energy, and a loss of appetite. Rascal was not looking good, and his owners were preparing for the worst.

As a last resort, they tried to improve his appetite with hemp, and after finding a CBD retailer online, they started using their CBD capsules.

Within a few months his owners report that Rascal is like a puppy again! His energy levels are back up, his appetite is back up, and his heart and lungs are back to normal!

His owners are so happy they found and tried CBD with Rascal.

These 3 dogs are just a tiny fraction of the amount of dogs who are seeing great results with this treatment. Thousands of other pets are seeing life changing results on their tumors, and various other ailments.

Which Product is Best for Dogs with Tumors?

holistapet cbd pet tinctureThere are countless CBD products on the market today, and it can be hard for pet owners to choose one over the other.

On my site, I review a variety of CBD pet products to help pet owners like you make informed decisions about their furry friend’s health.

We currently love CBD products by Honest Paws and HolistaPet, and highly recommend them both.

For treating tumors, a top choice would be HolistaPet's CBD Tincture. It's one of the best selling options right now.

Honest Paws' Purity Level Oils would be another great option to pick. My dog saw great results with this CBD oil, and I think it offers great value right now.

You can read about my experiences with these brands by checking out the reviews.

Blake Armstrong
Blake Armstrong

Hey I'm Blake, the founder of this website. Our family was fortunately to have discovered CBD products after our dog Rosie was diagnosed with a few common ailments. I truly believe they enhanced her last few years, and it's my passion to spread the word through this website. Thanks for visiting!