Capstar (nitenpyram) Reaction / Warning.

Floodx4

TCS Member
Thread starter
Kitten
Joined
Jun 11, 2019
Messages
3
Purraise
4
Last Friday (6/7/19) I gave 3 out of our 4 cats a Nitenpyram capsule, a generic brand of Capstar sold under the name QUICK CAPS by Puppy Butts pet supply. Prior to giving them the medication, I did a fair amount of research, particularly on the brand. I realize now that I probably did not do enough research, or more specifically, did not do the "correct" research. To be 100% fair, I do not know if this issue is with the brand, or with the Nitenpyram medication itself.

After giving the medication to our cats, they all experienced the "Tickle Effect" as I have seen it called ... which is a very "cute" way of describing that they all completely FREAKED OUT! This reaction was expected, but I was not expecting it to be as severe as it was. All three cats seemed more "traumatized" than "tickled". They were switching back and forth from scratching, to running out of control, and back to scratching. At least one cat started panting for a few minutes that I observed. The severe reaction lasted about an hour. (This reaction is caused by the way the fleas die, and again was expected. There are a few good videos on YouTube that show how the fleas die, and explains why cats react this way)

After the initial "crazy" stage, all three cats had settled down to just "grooming" themselves, and we went to bed. And this is where the unexpected results begin. The next day, all three cats at first just seemed tired. One was laying on a loveseat, one was laying on bench, and the other was laying on my computer desk. AND THAT IS WHERE THEY STAYED UNTIL SUNDAY NIGHT!!! Yes, all three cats stayed in the exact same place for almost 48 hours! The did get up to use the litter box, and they did eat and drink, although considerably less than normal. Each cat would act "normal", but only when promoted too. (One cat LOVES treats, and he would take his treats, but only if I brought them to him, or picked him up and moved him to where his food is. Another cat is very lovable, and would cuddle and purr, but only if I picked her up. Her "normal" behavior is to follow me around the house wanting constant attention)

At first, I wasn't all that concerned. I was assuming that they were likely just tired from having the reaction to the medication, and had probably stayed up all night dealing with the last of the fleas dying. By Saturday night, I was getting slightly concerned, and by Sunday, I was getting VERY concerned. But, because they were still eating, drinking, and using the litter box, I just kept thinking that it was some kind of extreme fatigue, or maybe disorientation from the medication itself. I did look up and found that Nitenpyram should be out of their system completely within 48 hours.

By Monday morning, all three cats had returned "mostly" back to normal. At the least, they had moved from the spot they had been in all weekend. Then tonight (Tuesday) my fears have returned. Our male cat, Courage, had a seizure. He has had one seizure before, about 6 months ago ... so there is a chance this is unrelated to the medication. But he is now back to acting extremely disoriented and out of character. He wants nothing to do with the other cats, and has been searching the house for someplace to hide. He is also acting like his sense of smell is affected. (He is going to his food and smelling it, but not eating. He is going to his litter box and smelling it, but not using it). He is also going to the door wanting to go outside. (He has been a 100% indoor cat for almost a year, and has not acted like he wanted to go outside since).

I will be taking him to the vet first thing in the morning. He currently seems "stable", just very agitated, and definitely not acting normal.

I would caution anyone before using CapStar or Nitenpyram on their cats. I cannot say for sure that the seizure was caused by the medication, since he has had one before, but I can say that the medication definitely had some kind of effect on all three cats, that appeared to be some kind of effect on their mental state. It is certainly not normal for a cat to stay in the exact same spot (that is not a normal "spot") for over two days.

I said in the beginning that I had done some research, but not the correct research. If you look at the reviews for Capstar, or the generics on Amazon ... look at the 1 star and 2 star reviews, not just the 5 star, and you will see that a lot of people have had severe reactions to this medication, including losing their pets.
 

catsknowme

TCS Member
Top Cat
Joined
Jan 2, 2005
Messages
10,570
Purraise
5,173
Location
Eastern California,USA
:welcomesign: Welcome to TCS although I would that the circumstances would be better. :alright:
What a terrible experience for your kitties
Prayers and vibes that Courage is okay! :vibes::vibes::vibes:
I have been wondering what flea & tick medicine to use because my Maine Coon had a bad reaction to Frontline. Thank you for the warning.
 

lutece

TCS Member
Top Cat
Joined
Mar 8, 2018
Messages
4,498
Purraise
5,718
I'm very sorry that your cat had a seizure and is not acting normally!! That sounds very scary. Hopefully he will be back to normal soon!!

Unfortunately no medication is 100% safe, it is always possible for cats to react to a medication, and if you give enough doses to enough cats, eventually someone will have a bad reaction. Consequently, you will find horror stories online about every flea med, so it's hard to know what is safe! It's also hard to know for sure how a reaction is related to the medication... it's possible that your cats were reacting to the nitenpyram, but also possible that your cats' reaction had something to do with "Puppy Butts" generic formulation?

As far as flea medications are concerned, I personally feel more comfortable using Capstar than most other flea medications... it has a wide margin of safety in most cats and has been in use for a long time. I have used Capstar in kittens as young as 6 weeks, as well as pregnant and nursing cats; in some cases I have used it repeatedly to eliminate fleas; and I routinely use Capstar on the way home from a show so that I don't bring fleas home. I have used generic nitenpyram as well as the name-brand Capstar, and I have personally found the name-brand Capstar to work better and more reliably (although I still use generics because it's a lot cheaper). I am much less comfortable using some of the newer flea medications that don't have as much of a safety record. I personally try to avoid spot-on treatments, because I've seen many cats have reactions to them (and they aren't as effective, either)... but a lot of people have good results with them.
 
Last edited:
  • Thread Starter Thread Starter
  • #4

Floodx4

TCS Member
Thread starter
Kitten
Joined
Jun 11, 2019
Messages
3
Purraise
4
I'm very sorry that your cat had a seizure and is not acting normally!! That sounds very scary. Hopefully he will be back to normal soon!!

Unfortunately no medication is 100% safe, it is always possible for cats to react to a medication, and if you give enough doses to enough cats, eventually someone will have a bad reaction. Consequently, you will find horror stories online about every flea med, so it's hard to know what is safe. It's also hard to know for sure how a reaction is related to the medication... it's possible that your cats were reacting to the nitenpyram, but also possible that your cats' reaction had something to do with "Puppy Butts" generic formulation?

As far as flea medications are concerned, I personally feel more comfortable using Capstar than most other flea medications... it has a wide margin of safety in most cats and has been in use for a long time. I have used Capstar in kittens as young as 6 weeks, as well as pregnant and nursing cats; in some cases I have used it repeatedly to eliminate fleas; and I routinely use Capstar on the way home from a show so that I don't bring fleas home. I have used generic nitenpyram as well as the name-brand Capstar, and I have personally found the name-brand Capstar to work better and more reliably (although I still use generics because it's a lot cheaper). I am much less comfortable using some of the newer flea medications that don't have as much of a safety record. I personally try to avoid spot-on treatments, because I've seen many cats have reactions to them (and they aren't as effective, either)... but a lot of people have good results with them.
We have used Capstar (both name brand, and generic) on our dogs for years. We live in the country, so fleas are a constant battle every year. This year has been the worst I can recall, presumably from the record rainfall we had, following a very mild winter. This was the first time I had ever used it on the cats. Normally, just combing them, and an occasional bath keeps them bug free. This year, we are losing the battle with the bugs on the dogs, and it crossed over to the cats.

We have usually used generic medications when they were available, and until this situation, have never had a problem. I always do my best to research anything they get, and the Quick Caps seemed to have very good reviews on multiple sites. At worst, I had expected it to just not be as effective as Capstar.
But with it effecting three cats, all in nearly the same way, I have little doubt that there is something wrong with the medication. Oddly enough, Courage is the largest and oldest of the three, and seems to have had the worst reaction.

Unfortunately, this is going to make the flea battle exponentially harder. We are having to use another instant flea killer on the dogs (Advantus) pretty much daily, along with their Vectra 3D monthly topical. I have sprayed as much of the yard as possible (we have over 5 acres mowed), and we have been spreading Diatomacous Earth and vacuuming every few days. I am going to talk to both my cat vet, and dog vet tomorrow and see if they have any other ideas, that won't require a second mortgage. Unfortunately, at almost $5 a dose, using name brand Capstar almost daily would be impossible.
 

posiepurrs

TCS Member
Top Cat
Joined
Jan 11, 2015
Messages
2,247
Purraise
4,582
Location
Western Massachusetts, USA
I hope your cats will be okay! I regularly use capstar (the brand - no generic) on the cats when I go to a show. I do this because we have dogs and I don't want to take any critters into the show halls that aren't supposed to be there. We use spot on treatments too. I have never had any type of reaction - maybe I have just been lucky. When I order any type of medications for the pets, I am very careful of whom I order from since there are bogus medicines being sold on line.
 

darg

Gizmo
Alpha Cat
Joined
Jan 13, 2014
Messages
382
Purraise
320
I have no experience with Capstar other than the vet using it on my cat when he had surgery and required and overnight stay. It is the policy of the clinic. It scared the hell out of me, rationally or irrationally, because of an incredibly bad experience with an older, oral flea med back in the 80's (Proban). I have had an aversion and fear of using any oral flea med since. Again, that may be an irrational concern but that's the way I feel about it. I have no way of knowing what the effect of the Capstar was on my cat. I couldn't observe him for the first 24 hours as he was in the clinic, and he was post-op when he got home so wasn't quite himself for a couple of days anyway. But he did come through it ok and returned to normal a few days after the surgery so, at least, the Capstar didn't do any harm.

I'm sorry to hear about your cats reactions. I hope they end up getting it out of their systems and return to normal.
 

maggiedemi

TCS Member
Top Cat
Joined
Mar 26, 2017
Messages
14,073
Purraise
32,863
I've tried both Capstar and the Generic form of it a few times. My cats didn't have any bad reactions, but it didn't work. I needed something like Frontline, which kills the fleas continuously.
 

PushPurrCatPaws

TCS Member
Top Cat
Joined
May 22, 2015
Messages
9,763
Purraise
9,907
... But with it effecting three cats, all in nearly the same way, ...
I have never used Capstar on any of my cats, but I have heard that as it kills the adult fleas in the first hours, causing the cat or kitten to truly go bananas -- the fleas do not die peacefully, and they run around on the animal and bite a lot while they die. But it looks like you already were anticipating that.

So, I'd guess if I had an animal that I knew a lot of fleas, I'd consider using another flea med at the outset. That would whittle down the animal's adult flea population a bit, and then using Capstar wouldn't be as itchy and painful an experience for the cat or kitten.

I think there are different dosage strengths for Capstar. For smaller animals, the 11.4 mg of nitenpryam. The only thing I wonder about is if you used the lower dose of Capstar on the cats, or used the higher dose? If the latter, it would probably cause some of the lethargy symptoms you saw. I don't know. :dunno:


... Our male cat, Courage, had a seizure. He has had one seizure before, about 6 months ago ... so there is a chance this is unrelated to the medication. ...
... Oddly enough, Courage is the largest and oldest of the three, and seems to have had the worst reaction. ...
When Courage had a seizure 6 mos ago, was the vet able to figure out a cause? It could be an ongoing health issue and also since he is the oldest cat, maybe Capstar is just not for him as some of the more adverse effects would be risky for him.

There's a pdf you can dowload from their site ( pdf at link "See Product Label"), Capstar® for Dogs & Capstar® for Cats | Where to Buy


:grouphug2:
 

Kieka

Snowshoe Servant
Staff Member
Forum Helper
Joined
Sep 6, 2016
Messages
10,099
Purraise
14,980
Location
Southern California
I tend to stay away from generic flea control options just because they seem to have more problems. I know the generic topicals can be more dangerous in general then their name brand counterparts.
 
  • Thread Starter Thread Starter
  • #11

Floodx4

TCS Member
Thread starter
Kitten
Joined
Jun 11, 2019
Messages
3
Purraise
4
I have never used Capstar on any of my cats, but I have heard that as it kills the adult fleas in the first hours, causing the cat or kitten to truly go bananas -- the fleas do not die peacefully, and they run around on the animal and bite a lot while they die. But it looks like you already were anticipating that.

So, I'd guess if I had an animal that I knew a lot of fleas, I'd consider using another flea med at the outset. That would whittle down the animal's adult flea population a bit, and then using Capstar wouldn't be as itchy and painful an experience for the cat or kitten.

I think there are different dosage strengths for Capstar. For smaller animals, the 11.4 mg of nitenpryam. The only thing I wonder about is if you used the lower dose of Capstar on the cats, or used the higher dose? If the latter, it would probably cause some of the lethargy symptoms you saw. I don't know. :dunno:
When I gave them the medication, I had read about the "Tickle Effect", but I wasn't expecting it to be as severe as it was (or at least looked). I honestly didn't think they had that many fleas. With both dogs on a monthly topical, and giving them Advantus every few days, along with the dogs, cats, and house getting treated with Diatomaceous Earth, I wasn't expecting there to be a lot of them. I do get the feeling that there were more than expected, and that may have caused the initial reaction to be so dramatic.

As for the dosage, I did get the 12 mg capsules for the cats. Courage was given a full capsule, since he is almost 10 lbs. The other two cats were given a 1/2 capsule, since they are both under 5 lbs.





When Courage had a seizure 6 mos ago, was the vet able to figure out a cause? It could be an ongoing health issue and also since he is the oldest cat, maybe Capstar is just not for him as some of the more adverse effects would be risky for him.

There's a pdf you can dowload from their site ( pdf at link "See Product Label"), Capstar® for Dogs & Capstar® for Cats | Where to Buy


:grouphug2:
The original diagnosis was really a "no diagnosis". When he was at the vet (The next day), he was completely fine. The vet just did a basic wellness check, and everything was good. Since this was his first seizure, I was just told to watch him, and if he had another, to try to observe what happened just before it started. Unfortunately, we didn't see the start of this last one either.

We didn't go to the vet today, but did call and make an appointment for tomorrow. Since he is acting mostly normal, the vet didn't think it was an emergency, and he was booked solid today.

So far, he and the other two seem OK, but do seem to be just a little "off" still. I am starting to wonder if it is more of a mental reaction than physical. Courage has been staying behind one of the monitors on my desk, unless I coax him out, which is where he stayed for about a week after he first came inside. The other two are also keeping much more to themselves than normal.
 

Deborah Mahoney

TCS Member
Kitten
Joined
May 4, 2021
Messages
2
Purraise
2
Last Friday (6/7/19) I gave 3 out of our 4 cats a Nitenpyram capsule, a generic brand of Capstar sold under the name QUICK CAPS by Puppy Butts pet supply. Prior to giving them the medication, I did a fair amount of research, particularly on the brand. I realize now that I probably did not do enough research, or more specifically, did not do the "correct" research. To be 100% fair, I do not know if this issue is with the brand, or with the Nitenpyram medication itself.

After giving the medication to our cats, they all experienced the "Tickle Effect" as I have seen it called ... which is a very "cute" way of describing that they all completely FREAKED OUT! This reaction was expected, but I was not expecting it to be as severe as it was. All three cats seemed more "traumatized" than "tickled". They were switching back and forth from scratching, to running out of control, and back to scratching. At least one cat started panting for a few minutes that I observed. The severe reaction lasted about an hour. (This reaction is caused by the way the fleas die, and again was expected. There are a few good videos on YouTube that show how the fleas die, and explains why cats react this way)

After the initial "crazy" stage, all three cats had settled down to just "grooming" themselves, and we went to bed. And this is where the unexpected results begin. The next day, all three cats at first just seemed tired. One was laying on a loveseat, one was laying on bench, and the other was laying on my computer desk. AND THAT IS WHERE THEY STAYED UNTIL SUNDAY NIGHT!!! Yes, all three cats stayed in the exact same place for almost 48 hours! The did get up to use the litter box, and they did eat and drink, although considerably less than normal. Each cat would act "normal", but only when promoted too. (One cat LOVES treats, and he would take his treats, but only if I brought them to him, or picked him up and moved him to where his food is. Another cat is very lovable, and would cuddle and purr, but only if I picked her up. Her "normal" behavior is to follow me around the house wanting constant attention)

At first, I wasn't all that concerned. I was assuming that they were likely just tired from having the reaction to the medication, and had probably stayed up all night dealing with the last of the fleas dying. By Saturday night, I was getting slightly concerned, and by Sunday, I was getting VERY concerned. But, because they were still eating, drinking, and using the litter box, I just kept thinking that it was some kind of extreme fatigue, or maybe disorientation from the medication itself. I did look up and found that Nitenpyram should be out of their system completely within 48 hours.

By Monday morning, all three cats had returned "mostly" back to normal. At the least, they had moved from the spot they had been in all weekend. Then tonight (Tuesday) my fears have returned. Our male cat, Courage, had a seizure. He has had one seizure before, about 6 months ago ... so there is a chance this is unrelated to the medication. But he is now back to acting extremely disoriented and out of character. He wants nothing to do with the other cats, and has been searching the house for someplace to hide. He is also acting like his sense of smell is affected. (He is going to his food and smelling it, but not eating. He is going to his litter box and smelling it, but not using it). He is also going to the door wanting to go outside. (He has been a 100% indoor cat for almost a year, and has not acted like he wanted to go outside since).

I will be taking him to the vet first thing in the morning. He currently seems "stable", just very agitated, and definitely not acting normal.

I would caution anyone before using CapStar or Nitenpyram on their cats. I cannot say for sure that the seizure was caused by the medication, since he has had one before, but I can say that the medication definitely had some kind of effect on all three cats, that appeared to be some kind of effect on their mental state. It is certainly not normal for a cat to stay in the exact same spot (that is not a normal "spot") for over two days.

I said in the beginning that I had done some research, but not the correct research. If you look at the reviews for Capstar, or the generics on Amazon ... look at the 1 star and 2 star reviews, not just the 5 star, and you will see that a lot of people have had severe reactions to this medication, including losing their pets.
Hi,
Floodx4 said Quick Caps, not Capstar, was used. Quick Caps also contains Lufenuron.
 
Top