The Effects of Permethrin on Hair

Permethrin is an over-the-counter insecticide used to kill fleas and ticks in dogs. Permethrin is applied topically to the infested areas. Permethrin can be harmful if ingested. Call your veterinarian if you think your dog may have ingested the insecticide.

  1. Use

    • Permethrin interferes with the nervous system of fleas and ticks, killing them. Desired effects are seen 3-7 days after application.

    Side Effects

    • Skin irritation including itchiness and redness are possible side effects of permethrin use. Hair discoloration or hair loss at the point of application is possible.

    Warnings

    • Do not use permethrin on your cat, as she might ingest the insecticide while grooming herself. Do not use permethrin if your dog is sick or otherwise debilitated.

    Drug Interaction

    • Do not use with other flea/tick removal medications unless your veterinarian recommends it.

    Overdose

    • Vomiting, drooling, and diarrhea may be signs of permethrin overdose. Seizures and increased excitability may also be signs.