Vet Watch: Tips and pitfalls of dermatology in the new age of isoxazolines

Alice Jeromin, DVM, RPh, DACVD, and host Christopher Lee, DVM, MPH, DACVPM, open the premiere episode of Vet Watch with a comprehensive exploration of how isoxazoline parasiticides have revolutionized ectoparasite management in small animal practice. Jeromin begins by recounting the days when amitraz dips, pyrethrin sprays, and ivermectin baths were the mainstays of flea and tick control—treatments that demanded extensive clinic time, posed safety risks for both pets and handlers, and often yielded unpredictable outcomes. Lee adds that these older modalities frequently led to owner frustration and compliance issues, as many clients struggled with messy applications or adverse events such as chloracne or neurologic signs in sensitive breeds.

Jeromin then transitions to the modern era, where a growing suite of isoxazoline compounds—fluralaner, afoxolaner, lotilaner and sarolaner—have become the new gold standard for monthly or quarterly parasite prevention. Lee underscores that these molecules work by selectively binding to invertebrate GABA- and glutamate-gated chloride channels, inducing paralysis and death in fleas, ticks, mites and other arthropods, while sparing mammalian neuronal receptors. This selective mechanism not only affords an excellent safety profile but also delivers rapid knockdown of ectoparasites, often within hours of administration.

Beyond their core labeled uses for fleas and ticks, Jeromin highlights several extra-label applications that have garnered attention in veterinary dermatology. She describes how Demodex mange—once treated with lengthy courses of macrocyclic lactones or injectable organochlorines—can now be managed effectively with a single or monthly dose of an isoxazoline, reducing clinic visits and minimizing systemic toxicity. Lee contributes by noting successful control of Sarcoptes scabiei and Otodectes cynotis with similar protocols, often eliminating the need for off-label products like lime-sulfur dips or organophosphates. They also explore emerging data on isoxazoline efficacy against lice and even screwworms in endemic regions, suggesting a broadening spectrum of parasitic targets.

In the clinical setting, both specialists advise that veterinarians maintain a high index of suspicion for ectoparasites in any pruritic patient. Jeromin recommends routinely performing oil-based ear cytology to detect otodectic mites in chronic otitis patients, while Lee reminds colleagues that client education on proper administration—particularly feeding requirements for some products—is critical to achieving optimal drug absorption. They jointly advocate for year-round prevention, emphasizing that indoor-only pets remain at risk from hitchhiking ticks and fleas brought in on clothing or other animals.

Jeromin closes the discussion by challenging her peers to integrate isoxazolines more proactively into practice protocols, leveraging their safety, convenience and efficacy to improve patient outcomes and client satisfaction. Lee echoes her call, encouraging veterinarians to share success stories at local study groups and continuing education events, thereby advancing the standard of care across the profession.

Check out the episode above to hear the full dialogue and deepen your understanding of these transformative compounds. Your next challenging case of unexplained pruritus may have a simple, science-backed solution.

Alice Jeromin, RPh, DACVD—Before earning her DVM degree from The Ohio State University, Jeromin graduated from the University of Toledo with a BS in Pharmacy and practiced as a hospital pharmacist. She completed her veterinary dermatology residency with Patrick Breen and dermatopathology training at Procter & Gamble, Miami Valley Labs, as well as a fellowship in human dermatology at Metro Health Medical Center, Cleveland, Ohio with Bryan Davis. Jeromin is currently an adjunct professor at Case Western Reserve University, lecturer at Northeast Ohio College of Pharmacy, and former practice owner of Veterinary Allergy & Dermatology, Inc. She is a former member-at-large on AVMA’s Council on Biologicals and Therapeutics as chairman of the supplements and compounding committees. Along with publishing in human and veterinary journals, she authored the dermatology chapter in “Pharmacotherapeutics for Veterinary Dispensing”. Her interests include human-animal comparative dermatology and skin lipid research with publications in both areas. Because of her pharmacist background of counseling patients, she is a strong believer in client education and maintains her website, www.purrfectpet.com, for clients to be educated with evidence-based information as well as her podcast “Speaking of Pets” The podcast is geared toward pet owners of allergic pets to provide them with accurate, evidence-based information.