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Featuring Demian Dressler, DVM and Sue Ettinger, DVM, Dip. ACVIM (Oncology), authors of The Dog Cancer Survival Guide

The Oncologist’s Perspective on Chemotherapy and Gastrointestinal (GI) side effects: Part Two

Updated: October 10th, 2018

In my last blog post, I told you that most vomiting and diarrhea associated with chemotherapy was mild and could be managed at home. Unfortunately, there are exceptions.

Typically if your dog is vomiting, you will be instructed to hold on food and water to rest the GI tract for 12 to 24 hours.  But if your dog vomits multiple times (more than five) in a few hours, he is likely dehydrated, and this will only worsen during the period that we are withholding water by mouth.  He also likely won’t respond to oral anti-vomiting medications at home if he is puking them back up, so hospitalization is typically required.

With IV fluids, we can quickly and effectively fix the dehydration while we rest the GI tract – no food and water allowed. In addition, we can give anti-vomiting medications and antibiotics in an injectable form, so we don’t upset the GI tract further with the oral forms of medications.

Hospitalization is always a bitter pill to swallow. I typically tell pet Guardians that the chance your pet will be hospitalized with serious side effects is less than 5%. But once they are getting admitted, it is 100% for your pet. And I know you don’t want to leave your pet. I would also prefer every moment to be spent at home. But there are a few things to remember:

  • Chemotherapy side effects are temporary. With early intervention and comprehensive supportive care, the GI tract will heal and your dog will feel better soon, often within a day or two. I plead with you to NOT euthanize your pet now. If you have decided to treat with chemotherapy, support them through the hospitalization and then decide what to do. It is remarkable even to me what a difference a day make with IV fluids and supportive care.
  • Secondly, if your pet does get sick, chemotherapy can be continued. Yes, the same drug can be given, with adjustments.  The dose will be decreased and preventative medications like antibiotics, anti-vomiting, and anti-diarrhea medications to prevent another serious complication will be used. Repeat complications are highly unlikely in my patients. That’s why your dog should be under the care of an oncologist that manages a high number of chemotherapy patients and has expertise with the drugs and their side effects.

Charlie is an awesome Golden Retriever I am treating with the UW (University of Wisconsin) protocol for lymphoma. Earlier this spring, Charlie had multiple episodes of vomiting and diarrhea in the days following his first dose of vincristine.  When he came in on emergency at my hospital the Animal Specialty Center, he was too weak to stand and quite dehydrated. He had a fever and his white blood cell count was low. Charlie was admitted and spent two days under my care on aggressive IV fluids, antibiotics, anti-vomiting, and anti-diarrhea medications.  Within a day his white blood cell count was rebounding, and Charlie recovered.  We delayed his next treatment a few days, but the good news was his lymphoma was responding.

As you would expect, Charlie’s mom was quite concerned about giving Charlie vincristine again. Dogs get 8 doses of vincristine in the protocol. I told her repeat complications are uncommon, but she was obviously nervous. Well Charlie received all subsequent 7 doses, at a reduced dose and with preventative meds, and never had another complication from vincristine.

I am happy to report Charlie completed his protocol last month and was doing great at his one month follow up recheck last week. I cannot wait to see them both next month. Mom could not believe he did not have another major complication. That is my job: as Charlie’s oncologist, I adjusted his treatments so he could successfully tolerate them. I always say the goal is for my patients to not only live longer, but live well. And Charlie is doing just that.

To learn more about GI side effects and ways to manage them, including full spectrum approaches, check out the Dog Cancer Survival Guide.

Leave a Comment

  1. Colleen on November 5, 2017 at 6:25 am

    Dr. Ettinger, First of all, I want to Thank you for this wonderful site. Our dog Bella received Epirubicin , and has been in the hospital for 3 days. We were unable to give her anti-nasea medication because of vomiting and diarrhea. Yesterday on our visit she looked strong and even went on a walk. After this, Bella regurgitated clear fluid. I wonder if this is from her IV fluids.? I enjoyed the story of Charlie. It gives us great hope. Thanks a million

  2. Diane C. Nicholson on December 3, 2011 at 3:56 pm

    Sue, what is Cody’s prognosis? How much longer will this dog likely live, having gone through this protocol?

    My late Belgian Sheepdog, Boo, was diagnosed with lymphoma at 13 years of age. I did nothing for her out of the ordinary, simply continued with her good diet and love. She lived for about a year on pain relief. And then the glands in her throat swelled to the point where she could no longer swallow properly. I asked for prednisone at that point and she lived, and lived well, for another 2 months.

    Now I have a 16 year-old spaniel/cattle dog. She was diagnosed with hemangiosarcoma (with a large, spenic tumor) and given 2 weeks to 2 months, tops. At about the same time, a friend’s dog was diagnosed with the same thing. He chose surgery and chemo, I did not. I had no intention of putting my dog through that.

    It’s been 10 1/2 months– my friend’s dog went downhill almost immediately they started chemo and finally died shortly after the protocol was complete. My dog, Suki, is alive and, although she seemed to have a few minor bleeds, is active and happy. If Suki had had chemo it would have been given credit for the long time she has had.

    Meanwhile, my friend is out many thousands of dollars and had to take his dog to emergency several times and leave her at the hospital. Suki has been at home with her family.

    Human chemotherapy only helps a 5 year survival rate by 2.1%. Why would we think that canines would do better?

    I understand that vets, like doctors, feel that it’s better to do something, even if its success rate is so low and its toxicity on the immune system, when it is needed the most, is so high. And the people who share their lives with these dogs are so inundated with things like “run for the cure” that they jump at the chance to do all that the medical community has to offer. Yet, with human cancer, nothing much has changed in 50 years. They’d like us to think it has, but when one looks closely at the stats, it hasn’t; not when it comes to the final outcome. The problem is, no one is talking about these dogs being cured, but only that it might give them more time. At what cost? We know that these highly toxic drugs actually cause other cancers among other problems caused by toxicity. Who are we doing this for? For the dogs’ people, who only want to do what they can but end up paying huge amounts of money often on their credit cards, gambling for extra time? For the dogs, who must endure trips to the vet, chemotherapy that often makes them ill, and the extra stress that the financial burden puts on their people, but might (and might being the operative word) get a little extra time on this planet? Or are we doing it for the pharmaceutical industry that looks constantly for even more targets for its drugs?

    My husband was diagnosed with colon cancer earlier this year. Surgery made sense to us but the radiation and chemo did not. There are 5 cancers that chemo works for with humans and it’s possible that, if one has 2 types of childhood leukemia, 2 types of lymphoma or testicular cancer, using chemo might make the toxicity worthwhile.

    I just find it difficult to hear the rah-rah stories but none of the actual final results. Even though the dog might be doing well a month later, we know that chemo in people, will kill all the cells except those that are the largest and most aggressive– hence the term, “The cancer came back with a vengence!” Does this not happen in dogs as well? Just the couple of dogs I do know who’ve had chemo, both died within a couple of months after the treatment was complete.

    Do we really believe in life at all costs, or should we consider quality (for the people as well as the dogs) instead of possible extra weeks or even days?



  3. AnnM on December 3, 2011 at 2:54 pm

    We recently lost our very special Keeshond Andie to stomach cancer although she lived 7 weeks after the dx. She was nauseated from the cancer and we had to coax her to eat the entire time. We used cernia injectable meds, but she continued to lose wt. We did use ginger per your additional notes with some success. Chemo was tried and really didn’t make her ill – I have had to treat 3 dogs with chemo and all of them lived longer than they would have and had very good quality of life. One even lived 14 months after her bladder cancer treatments for a total of 26 months which was pretty much unheard of 18 yrs ago. I tell people if there is any hope the dogs will respond to “go for it” as long as the dogs are comfortable. It is expensive, but with Care Credit much is possible. I just wish there was a really good protocol for stomach cancer which seems to be far more common nowadays -MUST be the food which is why I am working my way back to feeding our dogs a home made diet. Your book was a big help and 2 others have purchased it and are glad they did, after I told them about it.

  4. Chris on November 29, 2011 at 1:27 pm

    Dr. Sue,
    Yay black labs! Thanks!
    Dr. Chris

  5. Chris on November 21, 2011 at 3:14 pm

    Hi Dr. Dressler and Dr. Ettinger,
    Thank you for creating this blog. I’m sure many owners are finding it an invaluable resource. I’ve written a blog about my dog Cody and have shared it with many of my clients. I’ve gotten some good feedback and would like to share the link here if you approve. The site is:
    Dr. Chris Hansen

    • Dr. Susan Ettinger on November 27, 2011 at 10:10 am

      Dr Hansen,
      Thanks for your feedback. I was just reading your blog and your experiences with Cody. I know it is overwhelming – hard to be his mom and his vet, I am sure. He is lucky to have you, and I thank you for sharing his story with your readers – now including me! Good luck with his treatment!
      PS. He is a very handsome boy! I too have a black lab.
      Warm regards, Dr Sue

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