Permethrin (Bio Spot-Spot On for Dogs, K9 Advantix)
Veterinary & Aquatic Services Department, Drs. Foster & Smith


Permethrin is an insecticide which kills fleas and ticks, and may also kill other insects. It is generally applied as a once-a-month spot-on. The product must be applied to the skin (not the hair) for it to be effective. Do NOT use on cats. In cases of adverse reactions, wash the pet with a mild shampoo and warm water to remove the product. Contact your veterinarian if your pet experiences vomiting, diarrhea, incoordination, increased excitability or seizures after being treated with permethrin.

Generic Name

Brand Name
Bio Spot-Spot On for Dogs, K-9 Advantix

Type of Drug

Form and Storage
Topical oil (spot-on)
Store at room temperature.

Indications for Use
Treatment and prevention of flea and tick infestations.

General Information
EPA approved for use in dogs. Available over the counter. Permethrin is a manmade form of the naturally occurring pyrethrin. (Permethrins should NOT be used on cats.) Both interfere with the nervous system of the flea or tick paralyzing and killing it. May take 3-7 days for highest effect.

The topical spot-ons spread over the body with the body oils, and collect in the hair follicles and then are released over time (up to 1 month) from the hair follicles onto the skin and hair.

Usual Dose and Administration
Apply according to manufacturer's recommendations. The product must be placed on the skin for it to be effective.

Side Effects
May see skin irritation including redness, itchiness, rash, hair discoloration or hair loss at site of application. May see lethargy or drooling. Consult your veterinarian and bathe the dog.

Do not use on patients hypersensitive (allergic) to it.

Do not use on cats, or on dogs which a cat may groom.

Do not use on sick or debilitated dogs.

Consult your veterinarian before using on dogs with heart, liver, or kidney disease.

Do not allow product to contaminate the environment as it is toxic to aquatic life.

Consult your veterinarian before using on pregnant or nursing dogs.

Drug Interactions
Do not use with other flea/tick control products that are put on the pet (sprays, collars, other spot-on oils) unless directed by your veterinarian.

May see drooling, vomiting, diarrhea, incoordination, increased excitability, seizures, or change in body temperature (higher or lower).

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Keep this and all other medications out of the reach of children and pets.

If you think your pet has been poisoned...

Contact your veterinarian or one of the Animal Poison Hotlines (listed below) if you think your pet may have accidentally received or been given an overdose of the medication.

**ASPCA Animal Poison Control Center - 24-hour service available throughout North America.

1-888-4ANI-HELP (1-888-426-4435). $65.00 per case, billed to caller's credit card.

Follow-up calls can be made for no additional charge by dialing 888-299-2973.

There is no charge when the call involves a product covered by the Animal Product Safety Service.

**Pet Poison Helpline - 24-hour service available throughout North America for pet owners and veterinary professionals who require assistance with treating a potentially poisoned pet.

1-800-213-6680 ($59.00 per incident). Staffed 24-hours a day.

Updated 6/20/17

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