Weaning info? – Page 2 – Second Chance AIHA Dogs

Keymaster

Tamara,
To respond to you I need to draw some important differences in how Dr. Dodds approaches (and approached with Chance) bone marrow failure in a dog. It is significant to note that she has been recognizing and treating this condition for a very long time. In 2007 even my renowned Diplomate Vet specialist was confused by Chance’s bone marrow failure and could only offer a guess that it might be autoimmune related. But as far as treatment, he offered little help or hope and prescribed only prednisone. Chance was not responding to this treatment.

I have helped many owners since then whose dogs had severe bone marrow failure. Many of the vets they were working with appeared to not be cognizant of how and why this condition appears in dogs. Nor in some cases did they understand how to properly treat this. Thus it also appears that they could not fully understand canine physiological response to treatment.

In intractable cases of bone marrow failure in dogs, Dr. Dodds knows from experience that many dogs have an autoimmune component and often autoimmune hypothyroidism. Many vets first seem to jump to the conclusion that this is a form of cancer. That essentially bypasses a series of diagnostics that Dr. Dodds normally recommends first before immediately doing a bone marrow biopsy. She points to investigating autoimmune hypothyroidism, a drug the dog was recently exposed to, a recent vaccination, toxic exposure, recent surgery, hormonal influence, infection or injury. You and I have talked about how I felt, from reviewing his blood work, that he was undergoing a inflammatory response to something and I thought that his digestive problems were related. A benign tumor probably wouldn’t be directly related, but if a spider, bee or snake bite occurred in this location and became infected it is possible that one of these insults could enhance an autoimmune reaction.

Years ago, Dr. Dodds recognized that bone marrow failure in dogs could be caused by an autoimmune attack on the precursor cells (stem cells) of the bone marrow by the T-cell lymphocytes. In her early career she had been involved not only in veterinary science but also has an extensive resume working in human hematology and immunology. Her experiences may have exposed her to the use of cyclosporine to treat humans with organ transplants. Clearly her understanding of how this worked in humans prompted her to explore using it in dogs with bone marrow failure and AIHA.

So this brings me around to how Chance was dosed with cyclosporine by Dr. Dodds for his severe non-regenerative anemia and neutropenia. She used “pulse dosing” with him, something she often recommends for dogs with intractable bone marrow failure. This concept is sometimes used in dosing with herbs. The idea being that constant exposure to an herb or drug on a daily basis begins to blunt the response by the body. Giving a few days off between dosing seems to resharpen the bodies response to the drug.

So she first started dosing Chance at a “Loading Dose.” (10mg/kg) The recommended higher dose for Atopica quickly brings the blood level up to a therapeutic dose, “jump starting” the treatment by saturating tissues. But to this dosing she also added the pulse dosing, so he received his Atopica Monday through Friday and had a drug holiday Saturday and Sunday. After 3-4 weeks of this dosing schedule she had me reduce the Atopica to the normal dosing. She continued him on the M-F, SS off, dosing schedule. Within the first 3-4 weeks he became regenerative.

I often read that vets want to test the blood level of cyclosporine to ensure that it is in the correct levels. I have explained the history of this with human organ transplant to you already. There were two formulations of drugs and they were being used interchangeably. It was not apparent until after some time that one formulation had a much more variable absorption in the body and patients were sometimes not getting enough of the drug, thus the eventual required testing of blood levels. When they discovered this it was recommended that they use the formulation that was more stable and absorbed at a constant rate. This is the formulation they use in Atopica and generics of this drug now for dogs.

So it isn’t usually necessary to test the blood levels of this drug in a dog because they are receiving the correct formulation that ensures proper absorption as long as it is dosed according to the recommendations and is being properly given without food. I asked Dr. Dodds about this early on and she told me not to waste the money testing. We would know soon enough if this was going to work and in fact she was quite correct.

But secondly, think about how Dr. Dodds doses these dogs with bone marrow failure, she uses pulse dosing. Taking the drug away for two days in a row should negatively affect the therapeutic value of it, right? But it doesn’t and Chance is a perfect example of that. The drug was MORE effective being given only 5 days a week with two days off. This blows the whole concept out of the water that this drug is only effective at a certain daily dose (to maintain blood levels) and any dose below that it is not effective. Your vet is telling you that the drug is either on or off, that there is no level of efficacy at a lower dose. From my experience it maintains a proper blood level even with pulse dosing!

So yes, I did targeted decreases. I used a 33% reduction rate, approved by Dr. Dodds. I had to fiddle with this a bit because Atopica only comes in certain capsule sizes. I extended this decrease period out a little longer because Chance had allergies and I wanted to keep him on it into the worst allergy season in the following year. This drug is intended to be given to dogs for a long periods of time for allergies and has been tested to show that it is safe and effective dosing this way. So if this were my decision I would continue it and begin the decreases as I have described, 33% at a time.

If there is a relapse it will be less complex to just increase the dose some rather than go through a loading dose to get his blood saturated again.

I would recommend you reconnect with Dr. Dodds about the reduction. I would trust what she tells you.
my best
patrice

Details