5 Things Not to Do During Your Pet’s Cancer Treatment

By Dr. Joanne Intile, DVM, DACVM

Learning that your pet has cancer is devastating. Deciding on which, if any, treatment path to take is confusing and it is normal to feel anxious as you are making decisions for your pet. Owners frequently struggle with feeling a lack of control and search for options to enhance their pet’s prognosis during their treatment plan. While most of these choices are not harmful, sometimes an owner’s best intentions can unknowingly offset their pet’s progress. The following are suggestions of what to consider avoiding during cancer treatment to optimize your pet’s care.

Avoid starting your pet on any supplements or medications before talking to your primary veterinarian and/or veterinary oncologist.

You might be tempted to start your pet on supplements, vitamins, or other medications as part of a regimen to aid in their body’s defenses against cancer and to support them through their treatments. Most supplements do not undergo regulation regarding content. These products, which may be touted as “natural,” could negatively interact with your pet’s prescribed medications, reducing the benefit of chemotherapy and harming your pet’s system.

Owners are often surprised to learn that some of the chemotherapy drugs we administer come from plants and are therefore also classified as natural substances. The effects of interactions between different natural substances, such as with conventional medicine and alternative medicine/supplements, are unpredictable at best. Veterinarians who cannot guarantee that mixing the two would not lead to treatment failure or harm will honestly explain their concerns and advise you on how to proceed.

See Dietary Supplements and Cancer Treatment: A Risky Mixture to learn more about potential negative interactions between supplements and chemotherapy.

Don’t overfeed your pet.

Some pets with cancer, especially cats, will show signs of a poor appetite during treatment. This occurs because of the disease process itself and in response to the prescribed treatments. In those cases, veterinarians frequently lift the typical dietary restrictions placed on companion animals and permit owners to offer a wider variety of foods, including typically prohibited menu items such as fast food or other kinds of “people” food. But for pets whose normal appetites are not being affected by treatment, overfeeding them and/or routinely offering food items the pet would not normally ingest can cause gastrointestinal upset, which may mimic adverse signs from treatment, leading to confusion about how best to proceed. In addition, pets can easily become overweight even with minimal overfeeding, which can exacerbate previous orthopedic disease and lead to concurrent health problems, including cardiorespiratory disease and pain, resulting in a reduction in the pet’s quality of life.

While it’s understandable to want to keep your pet happy during this difficult time, it’s better to shower your pet with attention and toys and activity and not to overdo it with calorie-rich “comfort” foods.

Don’t be a loner.

You may encounter individuals who question your decision to treat your pet’s cancer, arguing that you’re being selfish or traumatizing your animals. Personally, I’ve been told countless times that treating pets with cancer is the equivalent of “torturing” them. Such harsh judgment can be isolating, making you second-guess your choices and intentions. Please find reassurance in knowing that there are thousands of owners who choose to treat their pets, just as you are, and these individuals can be your best resources for information and as sounding boards for you to express your concerns, questions, and frustrations.

Many owners of pets that have undergone cancer treatment are happy to provide insight and advice to owners considering their options. This may be in person or via the Internet. For example, Tripawds is an online community of owners of pets with three (or fewer!) limbs that is an excellent resource for owners considering limb amputation for bone tumors.

Skip the dog park (but only at the specific times outlined by your veterinary oncologist).

Pets receiving chemotherapy can experience temporary drops in their white blood cell counts at specified times following their treatment. During these periods where the immune system is being compromised, animals are more susceptible to infection. While the overall risk of illness is low, there will likely be times you should avoid situations where your pet might encounter new pathogens. This may mean occasionally missing a trip to the dog park or groomer, or keeping your typically outdoor cat indoors for a short period of time. In addition, reducing stress levels to a minimum during periods where your pet may have lowered immune defenses is of utmost importance. This means limiting houseguests (two or four legged) if your pet is the kind to become anxious in such situations, avoiding boarding your pet if you decide to travel (get a pet sitter to stay at your home instead), or taking your pet with you rather than leaving them alone if they have a tendency toward separation anxiety.

While such physical challenges may seem to cause significant negative impacts in your pet’s quality of life, the important consideration is that this change is truly temporary and will only be for a few days following certain medical treatments your pet receives.

Don’t be afraid to ask your vet questions.

You will likely have dozens of questions about your pet’s condition and treatment plan and it’s important to have those questions or concerns addressed as quickly and efficiently as possible. You probably won’t think of all of them right away, so writing them down as they occur to you is important.

While the internet is a valuable resource, internet writers do not know your pet personally. Your veterinarian and/or veterinary oncologist will be the most appropriate resource for your concerns. You should never feel that any question is insignificant, and if you are feeling that you or your pet’s needs are not being met, voice your concerns. This empowers you to make the best decisions about your pet’s care and to feel confident in the plan.

Some questions to consider:

  • What is the exact type of cancer my pet has and where in his/her body is it found?
  • What signs should I look for that could indicate disease progression?
  • How will I know if my pet is having a reaction to treatment?
  • What can I do at home to help my pet through treatment and what are the “triggers” I should use to know when I need to call my veterinarian?
  • What is the expected cost of treatment and further testing?


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