Common Flea and Tick Toxicity Questions and Answers

Audra Stillabower, CVT
Veterinary Information Specialist

Here at Pet Poison Helpline®, we receive a large amount of calls every season relating to common flea and tick products. A lot of these questions are similar in nature and I would like to address some of these questions to help in a potential toxicity situation.

Q:  I just applied a topical flea medication to my dog/cat and they managed to lick some of it off. Will this be toxic to them?

A: Flea squeeze on products contain active ingredient(s) and a carrier that helps the product stay on the skin. If an animal is able to lick the product when it is wet on the fur or scratches the area and then licks their foot, the bitter taste of the product can cause the animal to salivate, foam at the mouth, become nauseous or vomit. Also, some cats have been known to become agitated and run around the house. This is only due to the taste and systemic toxicity would not be expected. Normal treatment would be to feed the animal a tasty snack and entice them to drink water or flush their mouth with room temperature water. For cats, wet cat food, tuna or tuna juice can be given. For dogs, treats or water flavored with chicken or beef broth may help to flush out the mouth. The symptoms should be mild and self-limiting. You should try to prevent the animal from licking until the product has fully dried. Once dried, it should not cause the same reaction when licked. If you are still concerned about the product, you can bathe the pet fully in a liquid dish soap three times back to back to remove the product.

NOTE: If a dog has been treated with a Permethrin flea product and the cat licks the wet dog product off the dog or brushes up against the dog and then licks their fur, this can cause toxicity as cats are highly sensitive to Permethrin products. If a cat has been exposed to a dog flea product, then immediately contact a veterinarian, the emergency number on the product package or Pet Poison Helpline® at 800-213-6680 for assistance.

Q:  I applied a flea collar to my pet and they chewed it off and ingested some of the product. Should I take them to a clinic?

A: First and foremost, ingesting parts of a flea collar can cause a foreign body obstruction where the pieces of collar can become lodged in the stomach or intestines. If obstruction occurs, it is a medical emergency. Most collars will be visible on an X-ray so your veterinarian can see how many pieces of the collar are in the animal’s intestinal tract, how large they are and where in the body they are located.

For toxicity, most flea collars only cause stomach upset such as nausea, vomiting and diarrhea if ingested. However, collars containing Deltamethrin can also cause neurologic symptoms such as ataxia, hind limb weakness, tremors or hyperthermia. If your pet has ingested part of a flea collar, it is recommended to contact a veterinarian, the emergency number on the product package or Pet Poison Helpline® at 800-213-6680 for assistance.

Q: I gave my pet an oral flea medication containing Nitenpyram and now my pet is scratching, panting and acting agitated. What is wrong with my pet?

A: Nitenpyram products begin killing fleas within 30 minutes of administration. When the fleas begin dying off, the movement of the fleas on the animal can cause a “tickle effect”. Common symptoms of this are vocalization, agitation, scratching or panting. These symptoms are expected to be mild and self-limiting and not related to toxicity. If this occurs, you can brush the animal gently to help remove fleas and help with the sensations of the fleas on the skin. Normally this sensation will fade once the fleas have died off, commonly within a few hours. If the symptoms continue or other symptoms are seen, then a veterinarian should be contacted.

Q: I applied a flea product to my dog and now he is rubbing on the floor and furniture, his skin is twitching, he jumps like something bit him and he’s scratching. Should I remove the product?

A: Some pets can be sensitive to flea products containing Permethrin. Any active ingredient ending in       -thrin is a Permethrin product. Some animals have a response to Permethrins called paresthesia. Paresthesia is a “pins and needles” or tingling feeling to the skin which can cause shaking and shivering, twitching, agitation, biting at feet and tail and rubbing the body along the floor or furniture.  Sometimes these symptoms are mild and resolve on their own without treatment. Also, the fleas dying on the pet can cause some of the same symptoms mentioned which will also resolve once the fleas have died off. In severe cases, you can bathe the dog fully in liquid dish soap three times back to back to remove the product. Other treatments are:  brushing the animal gently to help with the sensation on the skin, placing Vitamin E oil on the application site to soothe the skin or by placing a cool compress on the application site up to 10 minutes at a time. If cool compresses are used, the animal should be fully dry and you should wrap the ice or ice pack in a towel to prevent the skin from becoming too cold. If you are unsure of the symptoms you are seeing, you should contact a veterinarian, the emergency number on the product package or Pet Poison Helpline® at 800-213-6680 for assistance.

Q: I accidentally applied a dog flea product to my cat, what should I do?

A: Some dog products, mainly Permethrins, are toxic to cats. If this is caught quickly, within a few minutes of application and the cat is not showing any symptoms, you can bathe the entire cat in liquid dish soap up to three times back to back to remove the product and then call your veterinarian for further assistance. If the cat is showing symptoms such as tremoring or seizing, the cat should be immediately transferred to a veterinary facility for treatment.

When faced with a potential toxicity situation, it is important to remember that there is help available. Each flea product should have an emergency number on the package to call. Your primary veterinarian or emergency veterinarians are available, and Pet Poison Helpline® is here to take your calls 24/7, 365 days a year. While serious adverse reactions to a product are rare, they can occur to any dog or cat. Before applying a flea product to your pet, consult with your veterinarian about potential side effects, dosing instructions and the best type of flea treatment right for you and your pet. You can also contact the company who makes the product for additional information. We hope you and your pet have a safe, flea-free year!