Deltamethrin/Deltamethrin Combination Products, Topical

What are topical deltamethrin/deltamethrin combination products?

Topical deltamethrin/deltamethrin combination products (brand names PetArmor®, Sentry®, Zodiac®, others) are synthetic pyrethroid insecticides used to repel mosquitoes and to kill fleas and ticks on dogs older than 12 weeks of age for up to 6 months. Products may also be used to repel and kill sandflies. It may be combined with pyriproxyfen or other insecticides.

It may be used off label (extra label) to treat other conditions in dogs. Many drugs are commonly prescribed for off-label use in veterinary medicine. “Off label” means the drug is being used in a way that has not been reviewed or approved by the U.S. Food and Drug Administration (FDA) or Health Canada. In these instances, follow your veterinarian’s directions and cautions carefully, as they may be significantly different from those on the label.

How do I give my pet topical deltamethrin/deltamethrin combination products?

• Topical deltamethrin/deltamethrin combination products come in an impregnated collar form. 
• Collars are worn around the neck continuously for up to 6 months. 
• Follow manufacturer’s directions on application and use.
• Allow space for 2–3 fingers to fit between the collar and neck. 
• Wash your hands after application.
• Avoid contact with eyes and mouth.
• The collar may be worn while swimming or bathing.
• Give this medication to your pet for the entire time prescribed by your veterinarian, even if it appears that your pet is feeling better.

This medication should take effect within several days, though full effects may not be seen for 2–3 weeks. 

What if I miss giving my pet the medication?

If you miss a dose, give it as soon as you remember, and then continue with the regular dosing schedule. If it is almost time for the next dose, skip the missed dose and resume the regular dosing schedule. Do not give the pet two doses at once.

Are there any potential side effects from topical deltamethrin/deltamethrin combination products?

Topical deltamethrin/deltamethrin combination products may cause the following side effects:

• Redness, itching, and/or irritation at site of application
• Fur loss 

The following reactions are rare, but if they occur, contact your veterinarian immediately:

• An allergic reaction such as irregular breathing, rash, fever, puffiness and swelling around the face
• Tremors, seizures

Drug sensitivities can develop over time with repeated exposure. Your pet may have no reaction after the first few doses, but may develop a sensitivity later. It is important to watch for signs of an allergic reaction over the entire course of treatment.

Other side effects may occur. If you notice anything unusual, contact your veterinarian immediately. This is a long-acting medication, meaning effects will last several weeks to months.

Are there any risk factors for this medication?

DO NOT USE in:

• Cats and aquatic species
• Dogs who are allergic to any of the components
• Dogs less than 12 weeks of age

USE WITH CAUTION in dogs who are:

• Weak, frail, and/or geriatric
• Pregnant or nursing
• Already receiving other flea and tick medication

Are there any drug interactions I should be aware of?

Certain medications should be USED WITH CAUTION when given with deltamethrin/deltamethrin combination products, including: 

• Other flea and tick medications

Be sure to tell your veterinarian about any medications (including vitamins, supplements, or herbal therapies) that your pet is taking before starting any new treatment.

Is any monitoring needed with this medication?

• Your veterinarian may schedule follow-up visits for monitoring. In this case, follow your veterinarian’s directions.
• At home, monitor for any abnormal changes. If any occur, discontinue the medication and contact your veterinarian.

How do I store topical deltamethrin/deltamethrin combination products?

• Store the medication in its original container at room temperature. 
• Keep medication out of reach of children and pets.

What should I do in case of emergency?

If you suspect an overdose or an adverse reaction to the medication, call your veterinary office immediately. If they are not available, follow their directions in contacting an emergency facility. Adverse effects should also be reported to the FDA or Health Canada.