Why does my cat freak out every time I put flea treatment on him?

Dear Siouxsie, Thomas and Dahlia:
I've been treating my two cats with Revolution (selamectin), which prevents fleas, heartworms, roundworms and ear mites, for a couple of years now. The 6-year-old has no problem with it whatsoever; I apply it in the fur at the back of his neck and he barely notices it. However, Ash, who's almost 2 years old, has a very strange reaction to it every time I apply it. He gets a huge fright and runs away to sulk, then lies in a defensive, crouched position with squinted eyes, nostrils flaring and ears pinned back. He flinches away from any human contact, and I have to 'introduce' myself to him as I would to a new cat before he's able to trust me enough to accept any petting, but he doesn't respond to it at all. A few minutes later, he's all defensive again and I have to start from square one.

This behavior usually lasts for a day or two, and it's so out of character for Ash because he's normally a very friendly, trusting and affectionate cat. The smell is quite strong and he loves attention, so until now I always assumed he was just being a drama queen, but I'm beginning to think maybe it's something more than that. Could he really be allergic to the treatment, or is he simply overreacting to the smell? And if so, why doesn't my other cat also find it so offensive? (They're both indoor-outdoor cats so I'd imagine their sense of smell would be quite well developed.) Any advice you could give would be greatly appreciated!
~ Jasmine

Siouxsie: There are a couple of reasons why cats would object to being treated with these "spot on" flea remedies. We know from experience that it's not very pleasant to have that smelly goop on the back of our necks -- Mama treats us with Frontline Plus, and we certainly don't like it! In fact, we try to lick it off, but we can't reach it. But we sure do like not having fleas and ticks, so we put up with the goop.

Thomas: The medicine could be irritating Ash's skin, it's true. If this were the case, you might see redness or raised bumps at the site where you applied the Revolution. As far as we know, cats don't often have allergic reactions to these products, but it is possible.

Dahlia: On the other hand, it's at least as possible that the strong smell is offensive to Ash. All of these remedies -- Frontline, Revolution, and Advantage -- do have a strong odor to them. And because we can't reach the stuff to clean it off our fur, it can be very emotionally irritating to be treated with the stuff.

Siouxsie: Even though these products do smell, not all cats will find the odor so awful that it affects their behavior. All cats have a strong sense of smell, but as with humans, some cats are offended by smells that don't bother others. This could certainly explain why Ash hates the smell and your other cat doesn't really care.

Thomas: The process of being treated with Revolution or other spot-on treatments can be traumatic, too. Being held down and having stuff squirted on your skin is not very pleasant. If Ash has had trauma related to veterinary treatment or abuse in his past (before he came into your life), the treatment could be triggering an emotional reaction.

Dahlia: Many people would think it's weird that cats can suffer from post-traumatic stress reactions, but it's totally true. Cats' brain chemistry and development is very similar to that of humans, and traumas early in life can "rewire" cats' brains as they can humans' brains.

Siouxsie: So, Jasmine, Ash's overreaction could be a result of one of these factors or a combination of them. But there are some things you can do to help.

Thomas: First, we'd recommend that you talk to your vet about Ash's reaction to the flea treatment. She or he might suggest that you try a different spot-on treatment product. Each of these products has a different active ingredient. While Revolution contains selamectin, Frontline contains fipronil, and Advantage uses something else altogether. This could eliminate the possibility of an allergic reaction.

Dahlia: Since your cats go outside, you'll want to make sure that whatever treatment product you use is water-resistant. If Revolution gives more protection against parasites common in your area, your vet may advise you to stick with that product. In that case, you'll need to try another approach to easing Ash's anxiety.

Siouxsie: If you change treatment products and Ash still freaks out, or if your vet advises you to stick with selamectin, the next step is to help Ash feel less traumatized by the whole process.

Thomas: First, work on changing your own attitude toward treating Ash. It's very possible that he's picking up on your anxiety about treating him. At this point you're expecting Ash to have a strong reaction to the treatment, and it's understandably upsetting that he's so traumatized. So you may be creating an emotional "feedback loop" with him.

Dahlia: If you can stay calm and focused before, during and after the treatment, this will help Ash to feel better about the whole thing. Remember to talk calmly to him and tell him how brave he is and how much you love him. Tell him that having the goop on his neck will keep him healthy and keep him from having itchy, nasty fleas on his body.

Siouxsie: That's what Mama does when she gives us the goop, or any other medicine. We don't like getting medicines, but because Mama's so calm and quick about it, we're not terribly bothered by getting gooped or pilled.

Thomas: Of course, it took her a while to get that way. I remember the day Mama had to give Sinéad worm medicine, and she brought her mama over to hold Sinéad while she gave the pills, and there was all sorts of drama and angst and foaming at the mouth, and Sinéad scratched both of them and ran under the bed and gave Mama the "I hate you" eye for days afterwards!

Dahlia: Then Mama read an article on how to give a cat a pill, and she tried that process the next time and it was so quick that nobody knew what had happened. Mama was so encouraged that now she's a pro at giving us all kinds of medicines.

Siouxsie: She's been successfully giving her sister-in-law's kitty eye goop for the last two days. And this cat hates all kinds of medicines!

Thomas: So, Jasmine, working on own your attitude really can change Ash's attitude, too.

Dahlia: And a drop of Rescue Remedy afterwards will also help. Bach Rescue Remedy is a flower essence designed to help people and animals cope with trauma. It's available in health food stores (in the US) and in drugstores (in the UK). Simply put one drop on your fingertip and stroke the top of Ash's head. It works wonders!

Siouxsie: The Rescue Remedy will calm Ash's nerves, and since you're giving it by means of loving petties, that can't hurt either.

Thomas: We'd recommend that you reverse the order in which you're treating the cats. If you've been treating the 6-year-old first, try treating Ash first. If Ash has watched his catfriend get "tortured" and then has to have his turn, the anticipation may be creating more anxiety for him.

Dahlia: Likewise, if Ash has been first, treat the other one first. Sometimes that little change in the dreaded routine can make all the difference in the world.

Siouxsie: We hope this helps, Jasmine. Please let us know how things turn out.

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