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

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

How Do I Choose the Right Toys for My Cat? Vet-Approved Tips & Guide

When you have a cat, you already know how important it is to make sure they have something to do. This is particularly...

Manx Cat Health Problems: 8 Vet-Reviewed Issues

It’s an easy task to fall in love with the Manx cat—their bouncy personalities, communication skills, easygoing temperament, and enjoyment of pets and...

10 Natural Home Remedies to Stop a Cat from Scratching & Clawing

A scratching and clawing cat is both annoying and destructive. Cats can easily ruin curtains, furniture, and even rugs if the behavior is...

12 Reasons to Love Cats: Interesting Facts You Need to Know

Cats are one of the most popular pets in the US, and about 46.5 million US households live with at least one pet...

More related

Male Tortoiseshell Cats: Do They Exist & How Rare Are They? Vet-Approved Facts

Cats differ from dogs in many ways, but one particularly unique way is that people often associate a particular color with the sex...

Paddock Park Animal Care Center: Heroes of The Pet World

Veterinarians, vet technicians, practice managers, rescuers, behaviorists, nutritionists, trainers, volunteers, and other animal professionals are the backbone of pet ownership. Helping pets and...

Is a Bombay Cat Hypoallergenic? Vet-Reviewed Allergy Facts & Tips

Bombay cats are not considered hypoallergenic. While no breed is truly hypoallergenic, some are known to produce fewer allergic reactions in individuals who...

Tidy Cats Litter Review in 2025: Recalls, Pros & Cons

Review Summary Although brand recognition does not equal quality or performance, Tidy Cats from Purina is one of the best-known names in cat...

Keep reading

6 Tuna Popsicle Recipes for Cats You Can Make Today (Vet Verified)

Many of us turn to frozen treats to escape the summer heat. However, most ice cream and popsicles contain ingredients that aren’t safe for cats to eat. Fortunately, your cat can enjoy their own versions of popsicles that will also...

Tuna Popsicle Recipes for Cats You Can Make Today

Do Cats Like Privacy When They Poop? Feline Preferences Explained

Cats may not value your privacy, especially when you’re just trying to sneak off to the bathroom. Maybe you don’t mind the four paws following you to the bathroom and having another living being watching you do your business while...

cat pooping in the litter

How Do I Tell If My Cat Is Constipated? 8 Vet-Reviewed Signs to Watch For

If you’ve noticed that there hasn’t been poop in the litter box for a few days (and your cat isn’t going somewhere else), it could mean that your cat is constipated. Some signs of constipation are more obvious than others,...

cat pooping on the grass

Feliway Pheromone Spray Review of 2025: Recalls, Pros & Cons

Review Summary Feliway Pheromone Spray – A Quick Look Calms Cats During Travel The main thing that the classic Feliway Pheromone Spray does well is calm cats during travel. Most cats do not do well in the car, and this...

Feliway Pheremone Spray Review

How to Get a Picky Cat to Eat: 9 Vet-Reviewed Tips

While many cats enjoy their food a bit too much and happily gobble up everything in sight, others are choosier regarding what they eat. Cats can be put off by something about their food, like its flavor or texture, but...

Tabby cat eating food from white bowl

Can Cats Eat Lemongrass? Vet-Reviewed Facts & FAQ

Lemongrass is a common ingredient in several meals. You can use it in marinades, stir-fries, spice rubs, salads, and pastes. However, if you’re using lemongrass in a meal, you should not share it with your feline, as it can be...

Can Cats Eat Lemongrass

I Can’t Find My Cat Anywhere in the House: What to Do Next & Useful Tips

Not being able to find your cat can be a scary experience, and it’s easy to slip into panic mode, but keeping a calm, cool head is essential when creating an effective plan to find your cat. The first step...

Woman looking for cat under the sofa

Can My Cat Breastfeed After Being Spayed? Vet-Verified Facts & FAQ

If you participate in a trap-neuter-return program for stray and feral female cats or you currently own a nursing cat, you may have thought about having her spayed. The process is crucial for stray and feral cats to prevent multiple...

Gray mother cat feeding kittens while taking a nap