Environmental risk of spot-on insecticides on pets
After spot-on application, imidacloprid and fipronil spread over the surface of the skin, where they are incorporated into the superficial epidermis and sebaceous glands, and slowly released via hair follicles. From here, they disperse widely throughout the household environment through pet hair, shed skin and direct transfer. People, especially children, are at risk from these neurotoxins when they pet and snuggle with treated animals.
Significantly, hand-washing resulted in these chemicals going down the drain for at least 28 days after an owner’s spoton application to their pet, with an estimated 4.9% of imidacloprid and 3.1% of fipronil applied to dogs passing down the drain. Also, bathing the dog and washing contaminated bedding led to environmental contamination. These insecticides have lethal and sublethal effects on aquatic insects that are a vital part of the food chain.
Governments need to take action to prohibit the use of these insecticides on companion animals. (For details, see Perkins, R. et al. Down-the-drain pathways for fipronil and imidacloprid applied as spot-on parasiticides to dogs: Estimating aquatic pollution. Sci Total Environ, 2024 Mar 20; 917:170175; pubmed.ncbi.nlm.nih.gov/38244617/.)
Dear Dr. Fox: I gave my 6-month-old female pug a generic flea/tick/heartworm medication. She has had two episodes of wobble head and listing to the right lasting four hours in the last two weeks. No help at any vet so far. Can I please have a recipe for the milk thistle detox that’s dose-appropriate for her? She weighs 11.1 pounds.
L.B. and Rosie, Attalla, Alabama
Dear L.B. and Rosie: If you check my website, drfoxonehealth.com, under the DOGS section you will find a lot of information about the risks of the insecticide mix you gave to your dog and the alternatives available.
I advise 3 mg melatonin before bedtime and around noon for a week, plus a teaspoon of coconut oil in the food twice daily, also for a week. This may cause loose stools but can help the detox process.
Milk thistle has been safely used for years to help the liver detoxify and repair itself. The tincture form is the best to use for dogs, as it may be digested more readily than the dried herb. The typical recommended amount is 1/4 teaspoon per 20 pounds body weight. Give this in a dropper by mouth twice daily for five to seven days.
After three to four days of giving these supplements, I would bathe your dog in a good-quality pH-balanced doggy shampoo, since some toxins may be excreted via the skin when given orally. When topical spot-on insecticides have been given, dogs should be bathed immediately. Regrettably this will contaminate the environment, as has been found when treated dogs contaminate freshwater ecosystems when allowed to go into streams and lakes. This is another reason why these chemicals should be prohibited, in addition to causing seizures in some dogs and even making them aggressive.
Send all mail to animaldocfox@gmail.com or to Dr. Michael Fox in care of Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO 64106. The volume of mail received prohibits personal replies, but questions and comments of general interest will be discussed in future columns. Visit Dr. Fox’s website at DrFoxOneHealth.com.