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Flea & Tick Products

Comparing Flea & Tick Preventatives

As veterinary professionals, our job is to help our clients compare the pros and cons to figure out what is best for their family situation. Regardless of the product chosen, we recommend using it consistently year-round. How do we know it is working? We should not find any engorged/embedded ticks or fleas/flea dirt on the pet. In general, side effects are uncommon when the product is used as licensed, but individual sensitivities have been reported. Beware of counterfeit and lookalike products sold online; please purchase preventatives from licensed veterinary pharmacies and distributors. Avoid “grocery store brands” such as Hartz and Sergeant. “Natural” products often have not been tested for safety and efficacy and have been associated with skin irritation and liver disease.

Spot-on Topicals (e.g. Frontline, Advantix) generally have oil-soluble active ingredients and spread out over the pet’s coat; it takes about 2 days after application for them to fully distribute.

Pros: Bugs are exposed to the active ingredient on contact and, in most cases, start dying before biting. Advantix contains a repellent ingredient that deters mosquitoes and flies in addition to fleas and ticks.
Cons: Monthly application, greasy spot for a couple days. Advantix is toxic to cats (cats should not have contact with dogs for 48 hours after application). The most commonly reported side effects are skin irritation or hair loss at the application site. It may not be suitable for households with young children or folks with chemical sensitivities.

Long-acting Collars (e.g. Seresto, Scalibor) have active ingredients similar to spot-on topicals that are released gradually by friction against the hair. It takes about 2 days after application for active ingredients to spread out over the coat.
Pros: Bugs are exposed to active ingredient on contact. Not stinky or greasy. Only need to change about twice a year. Costs about $10-16/month. Seresto is approved for cats!
Cons: Collar must stay on all the time. Based on available data ok for cuddling but not recommended for households with toddlers who might grab onto the collar. Scalibor is toxic to cats. Most commonly reported side effects are skin irritation or hair loss at application site. May not be suitable for households with young children or folks with chemical sensitivities.
Chewables (e.g. Nexgard, Simparica, Bravecto, Credelio) have active ingredients that circulate in the pet’s bloodstream.
Pros: Nothing on the surface of the pet (very popular for families with young kids or folks with chemical sensitivities).
Cons: Not recommended for pets with previous seizure history or food allergies. Overdoses have been associated with neuromuscular symptoms including seizures. Bugs have to bite to get a dose of the active ingredient; theoretically they die and fall off in a few hours but may be attached long enough to transmit some diseases.
Nexgard vs. Simparica: Nexgard and Simparica Trio (includes heartworm preventative) are approved for puppies over 8 weeks old. Simparica (original) is approved for dogs over 6 months old. Simparica kills bugs faster, and has better duration of potency through to the end of the month. Simparica costs less than Nexgard.
Any chewable can be combined with any topical during peak season or in areas with high tick burdens like the Cape and the Islands.