Get

In Your Inbox

Catster is reader-supported. When you buy via links on our site, we may earn an affiliate commission at no cost to you. Learn more.

Can My Cat Take My Dog’s Flea or Worm Medicine? (Vet Answer)

grey cat scratching itself indoors

Dogs and cats are plagued with similar parasites, including fleas, ticks, and certain worms. So, is it safe to assume that preventative options that work in a dog can also be administered to a cat? The answer is no. It is not safe to treat your cat with your dog’s worm or flea/tick prevention. Although parasitism looks similar between cats and dogs, cats can be very sensitive to certain medications and the dosing may be different between species. Let’s get into the important details below.

divider 2 cats

Why Cats and Dogs Can’t Share Flea/Worm Medicine: Pyrethrins and Pyrethroids

The biggest reason that it is not safe to administer dog flea and tick products to cats is that a large portion of canine preventatives contain pyrethrins or pyrethroids, which are chemically altered pyrethrins. These common insecticides are derived from Chrysanthemum cinerariaefolium flowers. Cats are highly sensitive to these compounds, and accidental exposure to pyrethrins or pyrethroids at high levels can be fatal.

Cats have a harder time processing pyrethrins and pyrethroids due to their altered liver metabolism. However, cats typically can tolerate products with low concentrations of pyrethrins.

Permethrin is a common pyrethroid that can be found in sprays, spot-on treatments, shampoos, and dips designed for flea/tick control. Additionally, pyrethroids can be found in environmental products as well.

Most often, toxicity associated with pyrethroids occurs following accidental exposure to spot-on products or dips containing high levels of pyrethroids or pyrethrins. Unfortunately, the results can be deadly.

Beige or cream coloured older cat resting on bed and scratching his ear
Image By: Lubo Ivanko, Shutterstock

Signs of Toxin Exposure

Signs of toxin exposure can vary greatly. Below are some of the signs that might lead to suspicion of exposure to a toxin.

  • Hypersalivation
  • Tremors
  • Seizures
  • Obtunded
  • Vomiting

Accidental Administration/Exposure

In the event that your cat is administered or exposed either orally or topically to a product designed for a dog, immediately call Animal Poison Control and your local veterinarian. They will be able to advise you on how to aid your cat.

In many cases, a bath and close monitoring in a hospital setting will be recommended. If your pet is experiencing abnormal signs, like tremors, seizures, vomiting, or other concerning signs, symptomatic care will be implemented.

Pyrethrin/Pyrethroid Treatment

Unfortunately, there is not a specific antidote to pyrethrin/pyrethroid toxicosis. The goal of treatment for a cat exposed to unsafe amounts of pyrethrins is decontamination and secondary support. Bathing can be used as a way to physically remove toxins from the skin, but this should only be done in a stable patient, as thermoregulation will be necessary.

Additionally, induced vomiting and gastric decontamination may be necessary if oral ingestion has occurred. If a patient is comatose, care must be taken to help regulate body temperature. Tremors and seizures should be appropriately addressed, and the patient should be closely observed by a veterinarian.

woman brought her maine coon cat to the vet
Image Credit: Gorodenkoff, Shutterstock

Always Read the Label and Drug Insert

There are numerous amounts of parasite medications available over the counter and through veterinary professionals. It is critical that the packaging is read very carefully to ensure that the weight, age, and species the medication is intended for are appropriate. Providing your pet with the wrong dose of medication could be detrimental or could provide inadequate protection in some scenarios.

Many brands offer species-specific preventatives. For example, Advantage II is available as a feline product and as a canine product. The active ingredients are the same; however, the amount needed to be administered to a cat varies from that of the dog.

Administering too much of a product could be detrimental. A general rule of thumb is that cat products should not be used on dogs, and vice versa. Many products that are not safe for cats will have a product warning visible on the box.

Keeping Your Cat Safe

Even if your cat is not administered a dog preventative, accidental exposures are still possible and problematic. Grooming or rubbing on a dog with a recent application of a pyrethroid-containing preventative could result in toxin exposure. To be safe, after administering a topical preventative to your dog, physically separate your cat from the dog for 72 hours, or for the duration of time recommended by the manufacturer.

divider 2 cats

In Summary

It is not recommended to administer a canine preventative to your feline companion. If this is done accidentally, the results could be devastating. Immediately contact your veterinarian and pet poison helpline for treatment recommendations. The prognosis is overall good for cats with pyrethrin toxicosis if treatment is quickly initiated. To be safe, carefully examine the product prior to administration. Always confirm that the species, age, and weight on the label are appropriate for your feline companion.

If you need to speak with a vet but can't get to one, head over to PangoVet. It's an online service where you can talk to a vet online and get the advice you need for your pet — all at an affordable price!

PangoVet_Mention-in-Content for PangoVet2 save money


Featured Image Credit: Susan Santa Maria, Shutterstock

Want content like this delivered to you?

Sign Up For Our Newsletter

News, insights, expert advice, and everything cat

* By submitting, you agree to our Terms & Conditions and Privacy & Cookies Policy.

How useful was this post?

Click on a star to rate (you can leave written feedback after clicking submit)

Help us improve Catster for pet parents!

Your feedback really matters.

What did you like about this post? Also how can we improve it?

Join the conversation

Leave a Reply

You’re very welcome to leave a comment or question. Please know that all comments must meet our community guidelines, and your email address will NOT be published. Let’s have a positive and constructive conversation.

Talk With A Vet Online

Peace of mind,
anywhere, anytime

Affordable vet advice

Sphynx Kittens for Sale in the USA: 2025 Breeders List

Excited Cats advocates for adopting before shopping, though we fully understand there are many reasons for seeking a breeder. So, we encourage it...

Can Cats Eat Animal Crackers? Vet Reviewed Facts

Picture the scene: You’ve stolen a few minutes to enjoy some animal crackers, and your cat comes over, settles at your feet, and...

My Cat Ate a Lily: Is It Dangerous? Vet Reviewed Signs & Treatments

Lilies are beautiful and fragrant flowers, seen in plenty of vases, bouquets, gardens, and displays around the world. Behind their beauty and grandeur,...

8 Different Types of Cat Treats: Vet-Approved Tips on How to Choose

There are a lot of cat treats on the market, so deciding which to get your feline friend can be challenging. Would they...

More related

8 Best High Fiber Cat Foods of 2025 – Reviews & Top Picks

As a pet parent, you undoubtedly love your feline companion. You ensure your cat has frequent vet visits, is groomed properly, and has...

10 Types of Cat Collars and Their Uses (With Pictures)

When most people think about cats, leashes and collars are often the last things that come to mind. Neither indoor nor outdoor cats...

9 Best High-Sided Litter Boxes for High Spraying Cats in 2025 – Reviews & Top Picks

Cleaning out litter trays probably isn’t on the list of any cat lover’s favorite tasks, but it’s something that we have to do!...

Can Humans Get Tapeworms From Cats? Our Vet Answers

Many studies show the benefits of owning cats, but they can come with a few risks, too. There are certain illnesses (called “zoonoses”)...

Keep reading

Low Blood Pressure in Cats: Our Vet Explains the Signs, Causes, Treatments & FAQ

Low blood pressure occurs less commonly in cats than high blood pressure does. Causes may include blood loss, severe infection, heart disease, or even side effects from medications. Cats with low blood pressure may have pale gums, weakness, behavioral changes,...

domestic striped kitten with a sad face feels sick

5 Types of Superfoods for Cats: Vet-Approved Foods to Benefit Their Health

There are various superfoods for cats that are available to help improve their diet and replenish their body with much-needed vitamins and minerals. Many of these superfoods are easy to access and can be found at most grocery or health...

top view of a cream maine coon cat eating dry and wet pet food from feeding dish

Are There Cats Without Whiskers? Vet Reviewed Facts & FAQ

If you’re a cat lover or even a casual observer, you’ve probably noticed that cats have long, delicate whiskers protruding from their faces. But have you ever wondered if all cats have whiskers? The Sphynx cat and other breeds with...

close up of cat whiskers

Can Cats Get Addicted to Catnip? Vet Approved Facts & FAQ

If you have a cat or two, you’ve probably heard about catnip, which is a plant that cats seem to enjoy more than any other. Catnip has some rather interesting effects on cats, to say the least. When exposed to...

cat-eating-catnip

Can Cats Eat Feathers? Vet-Reviewed Risks & Precautions

Feathers are included in various enticing cat toys, most likely because they are reminders of favorite prey animals of felines: birds. Whether a poor bird has fallen victim to your cat’s hunting expertise or you are worried about your kitty...

Can Cats Eat Feathers

How Many Muscles Does a Cat Have? Science & FAQ

If you know anything about cats, you know how athletic and graceful they can be. Their muscles help them with agility and give them extraordinary flexibility. So, you might wonder how many muscles a cat has to aid in their...

Cat muscle computer rendering

Do Female Cats Spray? Vet Approved Facts & FAQ

It’s a common misconception that only intact male cats spray. The truth is spraying is not a sex-specific feline behavior. Female cats can and do spray. Having a female cat that sprays at home can be frustrating, especially if you...

a white cat spraying the wooden gate

Why Is My Cat Licking the Floor? 6 Vet-Verified Reasons

Cats sometimes do the weirdest things, and licking the floor is just one way that cats confound their human servants. The good news is that this behavior is relatively normal, at least by cat standards, and has some benign causes....

cat lick the floor