Carcinogenic Chemo Drugs
ByOne of the biggest ironies I have encountered are carcinogenic chemotherapy drugs.
Sound odd to you? Well, I don’t blame you! When I first found out about it I was shocked. Medication used for fighting cancer actually increasing the odds for cancer later?
Now, before everyone gets reactionary, we have to temper this topic with the big picture. Chemotherapy has helped a lot of dogs live longer lives with good life quality. Let’s not forget that reality.
The problem is that this is an area of medicine where the treatments used can, at times, have real-life and quite severe side effects. This is simply a reality of conventional cancer care and needs to be accepted as the current state of affairs.
I discuss how to lessen chemotherapy side effects in detail in The Dog Cancer Survival Guide if you are interested in this topic.
Take cyclophosphamide (Cytoxan), a common chemo drug used in dogs. The truth is that this medication is a known human carcinogen, and the same was found in rodents. Here is some information on the topic.
Cisplatin is “reasonably anticipated to be a human carcinogen,” and is carcinogenic in lab rodents. Here is more for your review.
So what does one do with this information? How are we supposed to feel okay about the use of these drugs?
Well, the age of the dog has to be kept in mind. While nobody knows the exact timing of a possible cancer developing after exposure to these drugs, it likely takes a while. Although I cannot give real data, a guess could be 1-2 years or more.
So it would make sense that in a young or middle aged dog, one might reach for different chemo drugs, especially if a life expectancy may be more than one or two years after the cancer.
These are very tough decisions as nobody has a crystal ball. However, as your dog’s primary health care advocate, you should be advised of all the facts.
All my best,
Dr D
About the Author
Dr. Demian Dressler, DVM is known as the "dog cancer vet" and is author of Dog Cancer Survival Guide: Beyond Surgery, Chemotherapy & Radiation. Visit his blog and sign up free to get the latest information about canine cancer. Go to http://DogCancerBlog.com.
4 Comments
September 24th, 2009 at 8:50 am
Dr. Dressler,
My 3 year-old Shih Tzu has, at times, severe itching, especially her face which she rubs up against anything she can find. This can lead to causing her make scabs. After trying Temoril-P and Lucy ending up in the hospital, I am not willing to go that route again.
Can you advise or suggest something less harsh to combat itching, perhaps something natural from Whole Foods?
Thank you.
Valerie
September 26th, 2009 at 9:24 am
I am not a doctor and do not play one on TV (ha ha) but this is just what I have heard and experienced. I know when I adopted my dog she was itching and oozing from her eye and snorting. The itching was bad. I changed her diet to a good food instead of the food with by products and grain that she got at the shelter. She is no longer doing any of those things. I put her on a good dry and then went to canned and now feed raw with canned. Bad food I think is a big cause of itching. Have you tried a soothing bath with an all natural shampoo or something like oatmeal (Aveeno). You might want to look into a supplement I heard of called Betathym which contains beta sistosterol–acts like cortisone but without the side effects. Acts like anti-allergy and supports the immune system. I think Stinging Nettles can also act like a Benadryl for the itching. Spring Tonic contains Nettles and that is made by Animal Apawthecary, I think. BHI has a product called “Allergy”. You might also try spraying with deionized waster which would stop the itch instantly–like wiping the dogs face with a towel of deionized water. Again, I am not a doctor but just sharing things I have heard or done myself. Just make sure there is no disease present. My dog was treated for infection and in the end she had a grave disease called Cutaneous T cell Lymphoma—I don’t know your dog’s other issues—-just sharing for you to investigate for your pet.
September 26th, 2009 at 9:31 am
More thoughts–it is weird it is just on the face–is this a contact dermatitis of some sort–is she laying on something irritating? Is it anxiety where she has developed a habit of doing this? Was the dog checked for one of the types of mange which I think is seen on the face first?? Good Luck
February 23rd, 2010 at 7:35 am
I’ve been reading through different blogs and found this one on Cytoxan, I have had an underlying fear that this may have caused the brain cancer in my Weimaraner. Five years ago my husband very suddenly became sick with Polyarteritis Nodosa, a rare auto-immune neurological disorder where his immune system attacked his arteries to his nerves and muscles, his arms and legs became numb and limp in 10 hours, and have taken 5 years to regrow. In order to shut down his immune system, he took high doses of Cytoxan daily for 3-1/2 years. During this time my dog, who is a certified therapy dog, would carefully lay next to him in bed, with the top of his head next to my husband’s mouth, my husband breathing on the very spot where my dog’s meningioma or meningeal carcinomatosis developed. They spent many, many hours every day like this. I wondered at the time if this would hurt our wonderful dog, but it was such a great comfort for my husband who was struggling for his life, I felt that if something happened to our dog he would have gladly given his life for his master. I will never discuss this with my husband or anyone else, except now you in a venue my husband won’t see, but I have to ask – could this have caused my dog’s brain tumor? It might be important to know if my husband has to go back on the Cytoxan someday.