Frontline Plus makes dog act really weird

I have been using Frontline Plus for almost a year now. At first had no problems but then after about 6 months my dog got a taste of it ( it must not have been dry yet and he rolled around trying to get it off of him) and got a taste in his mouth... ever since then each time he gets it put on him he acts crazy... walks around in circles, acts very quiet and will not sit and lay down when asked... does not want to eat etc. He acts like this for the day or night and then is fine in the morning. Our vet is aware and still thinks it is safe and I should continue using it. Anyone else ever hear or experience anything like this??? Thanks for any advice or responses.

Asked by Madigan on Nov 23rd 2008 Tagged frontline, allergicreaction in Pet Products
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Your dog had a bad experience one time with it by tasting it....he is now acting out everytime you put it on....sounds like its in his head.....personally we have never had any problems with it and I don't think your vet would recommend staying on it if it was harming your dog

Member 761510 answered on 11/23/08. Helpful? Yes/Helpful: No 0 Report this answer

Bam-Bam, CGC

I have heard of it causing a burning sensation (like Vicks) and other stuff. Maybe try a different one like Advantage or Advantix? Or the oral one?
Good luck!

Bam-Bam, CGC answered on 11/23/08. Helpful? Yes/Helpful: No 0 Report this answer


I have used Frontline Plus on Deogie since he was a wee pup and have never had any problems. The actually amount of liquid in the applicator is very small and if placed properly, ingestion should not happen but if it does I can imagine it tastes horrible. Maybe try a different tactic when appling, try doing it while he is napping on your lap. You could try a different brand but if it's just the act itself it may not make a difference. Good luck to you.

♥ DEOGIE ♥ answered on 11/23/08. Helpful? Yes/Helpful: No 0 Report this answer

Zackintosh CJ

I do NOT think it is safe! Its the same as putting pesticide/poison on your kid! By all means QUIT using it! I have used only apple cider vinegar for flea/tick control on my dog since he was a puppy! He has only had 3 fleas all through this year, even in Texas, my neighbors had horrible fleas year round and they used frontline! I had a flea infestation with my old dog and I used frontline plus. It only kept fleas off for about 2 days. Even without an infestation I don't think it works. PLEASE listen to your dog, if he is doing all that then it must not be doing anything good for him! Dogs will react before humans know anything is wrong!

Zackintosh CJ answered on 12/23/08. Helpful? Yes/Helpful: No 0 Report this answer


We have been using Frontline Plus on our 65lb Shepard/Lab mix for the past 5 months.
Just yesterday for the first time I noticed her acting weird after applying it. She would not sit or lay still and was acting disconnected from us. She would lay down and then get up walk around in circles go to another room lay down and get up from there. This continued until we went to bed hours later. At that time she just still was not herself. If we pay enough attention to our animals they will tell us when something is not right with them. This product/chemical gets into the blood of the pet, that's how it works. It will be the last time we use it on our pet and we will be looking for a more natural option for the future. Thanks for your original post.

Member 794173 answered on 1/19/09. Helpful? Yes/Helpful: No 1 Report this answer


I started my dog bandit (golden retr. german shepherd mix) when he was 1 years old and at first did not notice anything then he started having problems with diarrhea off and on and adventually connected it to frontline plus. The next summer the first 2 months after I gave it to him he became very nervous and agitated, but by the next day he seemed fine. Then the next month he broke out in a rash and he continued to itch even though I followed the vets advice and gave him a bath in Dawn detergent. This year we changed vets and I described the situation. He told me to use K9 advantix assuring me it was totally different ingredients. I applied it in April and my dog went crazy pacing the floor for the next 12 hours. It has been almost a month and He is just now acting like himself. I will not give it to him again. I feel like I am poisoning him and it affects his nervous system.

Member 833833 answered on 5/6/09. Helpful? Yes/Helpful: No 0 Report this answer


The last 3 months we have been giving our yorkie frontline (same as we have for many years). He is 12 years old now. He never had a reaction before but he did have a liver shunt as a puppy through his first few years of life so his liver is not 100%.

I just realized today that after each of the last 3 treatments he has been walking around and pacing all day. Up most of the night. Listless and restless. This goes on for a few days to a week. Then he has been ok until the next treatment.

This could all be coincidence but tonight it hit me as I tried to figure out what we had been doing different before each occurrence. We live in the northeast so we just started Frontline again and all this started. We are going to stop treatment and see how he does the next few months off of it.

I suspect my liver compromised dog could have toxicity to whatever is absorbed since he cannot eliminate it like regular healthy dogs.

Member 846324 answered on 6/15/09. Helpful? Yes/Helpful: No 1 Report this answer


Like many of the people that responded my dog has been doing the exact same thing. This was my first time using Frontline and will be my last. She has had the same reaction to advantage. So I think I need to look into natural options.

There is a company called Fleabusters that I used many years ago that worked well.

Perhaps I will return to using their home system. None of my dogs ever reacted to it and the company claims it to be non toxic. My mother at the time had an auto-immune disorder and was highly allergic to everything but this product did not seem to bother her. Too bad it is so expensive and I am still living on student loans!!

Ginger answered on 7/14/09. Helpful? Yes/Helpful: No 1 Report this answer


That is crazy, that is exactly how my dog acts. I use K9 Advantix. He paces and can't sit still. I didn't put 2 and 2 together until now. I just put it on him this morning and he is really being weird. Now he is just standing in one spot looking at the ground. I don't think I will be using it anymore.

Thanks for posting that.

Member 983160 answered on 4/23/10. Helpful? Yes/Helpful: No 1 Report this answer


I have used it on three dogs, our beloved and missed English lab, our 1 1/2 year old Irish Setter, and our 1 year old beagle. Two never had any problems (and I don't think my pediatrician would suggest putting pesticide on the children, so let's keep it real), but the Irish Setter this year has been extremely hyper. Today I put it on him, and he instantly began pacing and panting. He did this for one day last time too, but the vet says it's okay, and no one seems to have heard of this before. He is on the low end of the weight range, but it seems odd that he immediately acted up today. He never had it in his mouth. I know setters are hyper anyway, but it's like he's been downing espresso! I will consider trying something else on him next time, but it's worked great on the other dogs. If anyone can advise an alternative for him, or has any similar experience or explanation, I'm all ears!

Member 998231 answered on 7/25/10. Helpful? Yes/Helpful: No 0 Report this answer


This is true my puppy acts the same way. Sophie is seven months and weigh 4 pounds. She hides under the bed and constantly rubs her back on things. She will not eat. It hurts me to see her this way. I'm using Simple Guard 3. This is a prescription that repels fleas, tick and mosquitoes.

Member 1046080 answered on 8/16/11. Helpful? Yes/Helpful: No 1 Report this answer


I have used frontline on my puppy 3 times I never noticed until this past third time how strange my dog would act after applying it. it takes about a day or 2 for him to react to it. At first it scared me i thought he could be sick or that something had scared him while i wasn't home. He seemed really paranoid. He didnt eat as much and would just stand in front of the patio window just looking at one spot, he wouldn't even sit down to do it.At first i thought it was something he could see outside but when i realized he had been doing it for the entire day it sacred me. I had been home from my classes being cancelled so I spent the whole day with him. He had been acting strange for a day or two prior to this but I didnt think much of it. At night it was worse bc he began walking around and just still standing by the window i closed the curtains and he just still stood there trying to look out. His behavior really worried me and the only thing that had changed in his routine was this.

Member 1128300 answered on 8/29/12. Helpful? Yes/Helpful: No 0 Report this answer