A brown and white dog pooping on the grass


Is diarrhea a common side effect of cancer treatment in dogs? What medications and dietary adjustments might help?

James Jacobson: Here’s a question that we get all too often and I don’t how to say this delicately so, I’ll just ask you.  What about diarrhea?  I know that diarrhea can be an issue if your dog has a cancer. Thoughts, Dr. Dressler?

Dr. Demian Dressler: It is common and it can be a consequence of not only the cancer but sometimes even the medications, the treatments that we use for cancer. It’s something that is unpleasant to the dog and also unpleasant to the guardian.  Good news, though we can do different things to help with diarrhea we can alter the diet and there are variety of different prescriptions and supplements available as well, that can help improve this condition.

James Jacobson: Dr. Ettinger in New York…

Dr. Susan Ettinger: Yeah! So diarrhea is definitely something that will come up when we’re talking about chemotherapy in dog cancer patients. Since chemotherapy damages rapidly dividing cells in our gastro intestinal track are filled with this rapidly dividing cell, vomiting and diarrhea definitely are common side effects.  So, I actually in all of my patients that will gonna start chemotherapy I do send them home with what I call “just in case medications” and that would be either an anti-nausea-med or an anti-diarrhea med because what I find is that really helpful if they have the medication.  I give them instructions on when to use it if they can get started on this medication pretty rapidly within maybe the first 12 or 24hours it can really shorten how long the patients having diarrhea and make it much easier for both the dog and for the guardian.

James Jacobson: What are some of the more common meds that you would use?

Dr. Susan Ettinger: I think, one of the more common ones and what’s nice about its relatively inexpensive and quite safe is a drug called metronidazole and the other name, the trade name is called flagel and usually we will do a 5 day course of that even if the diarrhea resolves. We can use it a couple of times during a chemotherapy treatment and sometimes we’ll just use it once or twice but it will definitely like I said shorten how long the diarrhea goes on and firm up that poop quite soon which makes everyone happy.

James Jacobson: Absolutely! Well, Dr. Ettinger in New York, Dr. Dressler in Hawaii, thank you so much.  A lot more information in The Dog Cancer Survival Guide.

Dr. Susan Ettinger: Thanks so much!

Dr. Demian Dressler: Thank you!


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