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My 8-week puppy got Hartz flea drops. Is it toxic? What should I do?

Updated on September 23rd, 2025

Help! I put the Hartz ultra guard drops on my 8 week old puppy. I washed him in Dawn after. What else can I do? I'm scared he will die

2 Answers

Most Helpful Answer

Answered By Dr. Melanie, BVSc MS

Veterinarian

Published on November 11th, 2017

You did the right thing by washing the Hartz off of him right away, as it should only be used on puppies 12 weeks and older. Keep an eye on him for signs of toxicity, which include excessive salivation, twitching, vomiting, depression, and muscle tremors. If you see any of those signs, take him into a vet immediately. I would wait a couple of days, and then apply the flea treatment program I will give you below. I would avoid giving Hartz at all. It's an extremely poor product, not very effective, and has caused a number of toxic reactions in dogs and cats. I would never recommend using it. I have a safe program that you can use on him now. First, I would give him Capstar. It's a one time pill that starts killing fleas within 30 minutes. Then follow up with a spot on treatment, such as Advantage or Revolution. This is a treatment that has to be used once a month. You will also have to disinfect the environment. Wash his bedding in hot soapy water, and vacuum the furniture and carpet surfaces. You can use a spray to kill fleas in the house, such as Indorex, or a flea bomb would work well to kill the fleas in the home. Good luck, I hope this helps!

4Pet Parents found this answer helpful

Related Answers from Veterinarians

Answered By Dr. Melanie, BVSc MS
Veterinarian
Published on July 27th, 2019
Hartz is a terrible product, and I would be very concerned this could cause a reaction. Please keep a close eye on your cats, and if you see excessive salivation, vomiting, paw flicking, ear twitching, diarrhea, depression, incoordination, or muscle tremors, they have to see a vet immediately. Because it was put on five hours ago, you can try to wash it off of them now.
1Pet Parents found this answer helpful

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Related Questions

Hartz flea treatment didn't work. How to get rid of dog fleas safely?

Unfortunately Hartz is a very poor product and extremely ineffective. I would not recommend using it again. You can give Bella Capstar. It's a one time pill that starts killing fleas in 30 minutes and it's safe to give now. I would wash her to try to get the oily residue off, but you can't give her another spot on treatment until two weeks have passed. During this two weeks, it is safe to give Capstar daily (only one a day) to keep killing the fleas. After the two weeks have passed, I would apply a better quality flea treatment such as Revolution or Advantage. Keep in mind as well you have to disinfect the environment. Wash her bedding in hot soapy water, and vacuum the furniture and carpet surfaces. You can use a spray to kill fleas in the house, such as Indorex, or a flea bomb would work well to kill the fleas in the home. I hope this helps!

Updated on September 23rd, 2025

Health & Wellness

My cat had Hartz flea treatment for an hour. Is it dangerous?

Hello & thanks for using Petco Pet Education Center, formerly Petcoach. Cats will often exhibit signs of toxicity within 30 minutes to an hour, so by you washing the flea treatment off so quickly & Cheeto has not shown any symptoms so far, he should be fine. Good job.

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Accidentally used flea shampoo on my puppy. What symptoms to watch?

Usually the symptoms are pretty immediate. If you haven’t seen anything within 2-4 hours she will likely be fine. Most often what you will see is neurological symptoms. Anything abnormal, get her to a vet ASAP. I’d wait about a week before applying any topical flea/tick medications at this point. Please stay away from Hartz products in general. They are not recommended. I suggest you talk to your vet about what products are best to use in your area.

Updated on September 23rd, 2025

My cat got Hartz flea treatment. Is it safe or should I wash it off?

I would not use it on my own cats. It is a harsh product on cats and I have seen a few clients have an intense reaction to it involving seizures and muscle spasms. I would instead use something like the Seresto collar. Best wishes.

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Should I use Pet Action flea drops and a Hartz flea collar together?

While some flea collars are generally safe to combine with topical flea medication, I do not recommend using either of those products on Khloe. Both are poor quality products that do not work well at all, and Hartz is especially poor. Many animals have had bad reactions to Hartz products, as well as still having problems with fleas. I can give you the flea treatment program I always recommend, which works very well and is safe for Khloe. First, I would give her Capstar. It's a one time pill that starts killing fleas within 30 minutes. Then follow up with a spot on treatment, such as Advantage or Revolution. This is a treatment that has to be used once a month. You will also have to disinfect the environment. Wash her bedding in hot soapy water, and vacuum the furniture and carpet surfaces. You can use a spray to kill fleas in the house, such as Indorex, or a flea bomb would work well to kill the fleas in the home. I hope this helps!

Updated on September 23rd, 2025

My dog licked Hartz flea drops. How long until I see signs of illness?

Most reactions from that medicine include drooling, shaking, tremors and seizures. If none of these are noted and she is walking and eating fine then you probably do not have anything to worry about. You can monitor for signs over the next 24 hours. In cases of reactions the best thing to do is bath the medicine off

Updated on September 23rd, 2025

My older dog's flea treatment failed. Can I reapply it safely?

It usually takes 3-6 months of consistent monthly application of a quality flea preventative to rid a flea infestation. The ingredient in the Hartz Duel Action topical is unlikely to work very well for fleas. I suggest using a product like Frontline Plus, Advantix, Bravecto or Vextra for fleas as these tend to work better in my experience. I suggest thoroughly bathing Lil Feet to get rid of the Hartz topical and then apply one of the products listed above. You should do this monthly for at least 3-6 months to get rid of the problem. If the infestation is really bad you may need to have your house treated. If you are still seeing many fleas after a month or so you should schedule an examination with your veterinarian. Good luck and thanks for using Petco Pet Education Center, formerly Petcoach!

Updated on September 23rd, 2025

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