CBD for Dogs with Cancer

Dogs have never been more cared for. Today’s owners are ready with the knowledge and compassion necessary to make sure their pets have all the love they need. Add in the latest developments in veterinary medicine, plus a wealth of new wellness products appearing in pet stores, and it’s easy to see why there are so many wise old dogs out there!

A growing, aging population means that canine cancer rates are increasing. Researchers estimate that around fifty percent of dogs over the age of ten will develop cancer at some point, with cancer being the leading cause of death in dogs of that age.

With cancer rates so high, the path through treatment looks different for every dog and owner—but, there is always a path. For a growing number of pet families, part of that journey now includes CBD oil.

In light of the recent rise in research exploring the potential effects of CBD (cannabidiol) on cancer in humans, CBD therapy is being used by dog owners across the globe to supplement their pet’s treatment plan, with the hope of achieving two specific goals:

  • Helping to slow their dog’s cancer growth, and
  • Improving wellbeing and quality of life during their dog’s treatment.

Let’s take a look at how CBD achieves these things, as well as a full overview of canine cancer today.

CBD is a beneficial therapy for many dogs, not a cure for cancer. CBD products should never replace conventional treatments, nor the recommendations of your vet.

Cancer basics

  • Cancer is the uncontrolled division of abnormal cells, occurring almost anywhere in the body. Cancerous cells often consolidate into a mass called a tumor.

  • Cancerous growths are usually unregulated and continuous. Healthy cells reproduce in order to replace dead cells or as a function of normal growth during childhood. Cancer cells grow when they’re not needed, and may damage or kill other nearby cells.

  • Tumors can be benign, which means they may continue to grow, but do not spread to other parts of the body. Benign tumors may require removal if they compress nearby healthy tissues.

  • But they can also be malignant, which means they’re able to invade and harm nearby tissues, and can spread to other parts of the body. Malignant tumors can be harder to treat.

Types of Cancer

Any tissue or organ in an animal’s body can develop cancer, but dogs (and certain breeds of dog) are more susceptible to a few specific types of disease:

Common Signs and Symptoms

Despite older dogs being at higher risk, cancer can occur in dogs of any age. The Veterinary Cancer Society estimates that around 25 percent of all dogs will be diagnosed with cancer at some point in their lives.

In other words, approximately six million new cancers are diagnosed each year, in dogs in the US alone. Thankfully, most of these cases will be highly treatable, especially when diseases are discovered at an early stage.

A key part of early detection is about close observation from owners—keeping an eye out for possible early warning signs or symptoms that can make a big difference in your dog’s prognosis, especially if they’re at a senior age.

Visual clues like abnormal lumps, cysts, swellings on your dog’s skin, or tender spots in their mouth, can sometimes be easier to catch. Other visual symptoms include sores that don’t seem to be healing, or bleeding and discharge from orifices.

Other symptoms require paying attention to a dog’s physiology and behavioral habits. Pups having difficulty moving their bowels, urinating, swallowing, chewing, or breathing definitely deserve a check up.

Similarly, pain from developing tumors in the mouth or gastrointestinal tract can lead to avoidance behaviours—either refusing to eat, or avoiding company altogether (weight loss is a related symptom here).

Lethargic behavior or general weakness can be another behavioral warning sign. Reluctance to move around, low energy levels, tense or aggravated behavior, and restlessness, all might indicate the presence of underlying pain or discomfort.

In fact, any noticeable change to a pet’s physical appearance, behavior, or daily habits should warrant a call to the veterinarian. In most cases, what looks like a worrying set of symptoms turns out to have a simple environmental or topical fix, but where there is something more serious, it’s worth repeating: early detection can seriously help your pet’s recovery.

Treatment Options

Cancer in dogs is treated on an individualized basis, and is dependent upon veterinary and owner preferences, breed, age, type of cancer, and advancement of the disease. Often, a treatment plan will include a detailed course of medications and involve more than one kind of therapy. The most common canine cancer therapies are:

  • surgical intervention

  • Radiation therapy

  • chemotherapy, and

  • immunotherapy

The primary goals of treatment are to halt cancer growth, send tumors into remission, and ultimately eliminate all cancer cells. At the same time, your vet will also introduce a secondary set of treatment goals designed to maintain quality of life and combat cancer symptoms, as well as any negative side effects from therapy.

This is where CBD oil enters the picture. For dogs living with cancer over an extended period, including those whom the complete elimination of cancer is not possible, CBD and other supplemental treatments provide a vital way of keeping things as normal as possible, allowing our four-legged friends to continue doing all of the things that make a dog’s life the best of all possible existences. Supplemental cancer therapies include:

  • herbal remedies

  • lifestyle changes

  • pain medication, and

  • CBD Oil

How Can CBD Help Dogs with Cancer?

Here’s a look at those two main treatment uses for cannabidiol: (1) directly affecting tumor growth, and (2) helping maintain quality of life.

1. CBD May Help Reduce Tumor Size and Growth

Initial findings suggest that CBD may act to directly limit the growth and spread of cancer cells. While this topic has yet to be explored in detail for dogs, CBD has been linked to helping mitigate cancer cell growth and even kill cancer cells in human and mice models of cancer.

CBD treatment and cancer cell reduction has been associated in studies of leukemia, colon cancer, and breast cancer, among others. It’s thought that CBD may act to suppress cell growth through a variety of mechanisms, including protecting DNA inside cells from oxidative damage, which can lead to cancer cell formation.

Other studies are suggesting that CBD may increase the efficacy of existing treatment plans when used as a concurrent supplement. A 2018 study showed that radiation alongside CBD dosing was more effective for killing pancreatic and lung cancer cells in mice than radiation therapy alone.

If substantiated, CBD should allow veterinary oncologists to reduce the amount of radiation used on dogs with cancer, thereby reducing adverse side effects on the healthy surrounding tissues.

A similar recent study found that CBD helped augment chemotherapy treatment in mice with pancreatic cancer. Specifically, data showed that mice treated with a combination of CBD and gemcitabine (a chemotherapy drug) lived almost three times longer as those treated with gemcitabine alone.

When it comes to CBD’s potential as a primary cancer treatment, further research is of course needed. But if preliminary findings are anything to go by, then there’s good reason to believe CBD will soon become a mainstream tool in the fight against canine cancer.

2. CBD Helps Minimize the Harmful Side Effects of Other Treatments

Beyond directly reducing tumor growth, CBD plays a wider and far more well-established role in helping dogs through the difficult side effects of chemotherapy and radiation—as well as the upset of a cancer diagnosis.

CBD will help to reduce pain and inflammation, as well as help with nausea and appetite, which is why many owners and veterinarians alike will recommend CBD in place of traditional pain medication. Pharmaceutical pain drugs such as non-steroidal anti-inflammatory drugs (NSAIDs) can sometimes cause unwanted side effects in dogs, especially in the gastro-intestinal system, making them a double-edge sword in many cases. Opioids, on the other hand, have a deserved reputation for fast tolerance formation and a potential for overdose.

Even when used in conjunction with traditional medication, studies have shown that CBD can work to enhance the power of pills, while at the same time doing away with the nausea and loss of appetite that can affect many dogs undergoing treatment.

At its worst, nausea can lead to strong food avoidance, weakening pups at the very moment they need to be at their strongest. CBD has been shown to help prevent nausea and vomiting for chemotherapy patients, not only in humans, but also in several different animals. The intestines are full of endocannabinoid receptors and transmitters (the receptors to which CBD binds), allowing CBD to get to work throughout the GI tract.

Of course, veterinarians should have the final word on all matters related to your dog’s health. But as an owner, you’re also in a position of knowledge when it comes to the needs and wellbeing of your pet. Given the wealth of anecdotal and scientific research showing CBD to be an effective and safe option for dogs, you may want to consider making CBD oil part of a holistic cancer treatment plan—one which will give your four-legged friend the best quality of life alongside more invasive interventions.


  • More dogs are living for longer, which means higher rates of cancer—especially skin, bone, and blood cancers.

  • Treatments for the major canine cancers are well established and effective. However, some therapies carry negative side effects, and not all cancers are operable.

  • For dogs living with cancer, the benefits of CBD dosing are fast gaining an impressive reputation.

  • A wide body of scientific and anecdotal evidence supports the use of CBD for reducing inflammation, anxiety, and nausea—all common side effects of cancer treatment.

  • More recent research indicates that CBD may even play a role in directly reducing the growth of tumors.

  • CBD can play a key role in a cancer treatment plan, but it is not a substitute for other treatments. Always consult your vet.