Hi Jen. Thanks for the welcome.
First of all, in re-reading my original post, I realized (and too late to correct it) that I stated something backwards, which I need to correct. Revolution
is an "insecticide" (kills fleas) but NOT a registered "pesticide" by the FDA. All of the harmful, carcinogenic flea products out there on the market are pesticides (as well as being insecticides) by category. Again to clarify: Anything that kills insects/fleas can be termed an insecticide, including natural products derived from citrus. But not all are labeled as "pesticides", the term restricted for the more powerful (and potentially dangerous) products. I hope that is clear.
As far as your case goes, I am interested to know more about it. There have been a number of reactions to selamectin listed, but as I wrote earlier, I have not seen in any in my practice other than hair loss.
Which brings up the topic of why this occurs: Why
do many, many individuals have no issues with a drug while a small group experience a side effect? This is actually a much more interesting question than many think. We usually write it off to being "the way things are" or "genetics" but those are very superficial and even "non-answers". I have actually done some research into this topic and found some interesting things.
One of the main reasons that one individual reacts negatively is the co-existence of other problems, such as the liver, kidneys or other organ not working properly. This is especially true of drugs/chemicals metabolized
or targeted by those organs. On the other hand, some individuals are subclinically ill with malnutrition and experiencing immune deficiencies, enzyme deficiencies, or the like that set them up for a reaction. This is MUCH more common than we realize and one of the reasons why food intolerants (e.g. those with celiac disease) are sooo prone to illness and drug reactions to those compounds used to treat their illness. It's like a catch 22. This is common, for example, among epileptics and their medications, which has become my specialty (the dietary control of epilepsy being the most remarkable discovery of my life).
But this now makes perfect sense. Those who are at risk to illnesses (e.g. allergies, "autoimmune disease" or cancer) are also the ones at risk to having adverse drug reactions, for many of the same reasons they are at risk to the disease they are fighting. Thankfully, much of this can be reversed using proper nutrition and avoidance of known triggers (drugs/vaccines/carcinogens).
So, when I have a pet who has an adverse reaction to a drug or vaccine, I don't just "treat" that by avoiding it in the future. I make a major note of it, make sure that I am not over-looking something important, and keep my eyes peeled for anything else that might need to be checked (e.g. thyroid, liver, blood cells). We know that the breeds of dogs that are most prone to vaccine reactions are the ones who will suffer the most immune mediated diseases down the road. Some of this may be due to the vaccines themselves, but as in the case of autistic children, there was likely to be something already wrong in that individual that set them up for that negative vaccine reaction. That's how you explain why millions of children get the same vaccine and have no problem. The vaccine WAS a major trigger in those cases but there
is a reason why that relatively small group reacted so negatively. Many of these same kids do phenomenally well on GFCF diets (gluten-free/casein-free diets) and this speaks to why they did so poorly after the vaccine. The food intolerance set them up for the catastrophic reaction to the vaccine.
This is also clearly the case in the dog, as the dogs that commonly react so negatively to vaccines are also from the most food allergic breeds, with food intolerance (e.g. gluten intolerance) being the reason they became allergic to that food (e.g. wheat). Dairy, soy and corn can all do the exact same as gluten, and that is why they are the top food allergens in pets and people....and why more and more pet food manufacturers are so proud to say that their foods don't contain them. (except for those who are deceived into thinking that corn is OK for dogs. It's not!)
I hope this helps,
John