FDA expands parasiticide label to include 2 additional ticks

Officials with the FDA have approved a label expansion for fluralaner for extended-release injectable suspension (Bravecto Quantum; Merck Animal Health). This parasiticide for canines now includes the treatment and control of the Asian longhorned tick (Haemaphysalis longicornis) and the Gulf Coast tick (Amblyomma maculatum) for 12 months with administration as a single injection by a veterinarian.¹

Fluralaner for extended-release injectable suspension was first approved by the FDA in 2025. It is also indicated in canines 6 months and older to kill adult fleas; treat and prevent flea infestations; and treat and control infestations of deer ticks (Ixodes scapularis), American dog ticks (Dermacentor variabilis), and brown dog ticks (Rhipicephalus sanguineus) for 12 months and lone star tick (Amblyomma americanum) infestations for 8 months.¹

Fluralaner is an isoxazoline antiparasitic drug. At the time fluralaner for extended-release injectable suspension was first approved, the FDA noted that several products containing isoxazolines were available for the treatment and control of fleas and certain ticks in dogs and cats. However, those products generally provide protection against fleas and ticks for 1 month.^2,3

“With Bravecto Quantum, Merck Animal Health continues to deliver the longest‑lasting protection available in a single dose—now covering an even broader range of clinically important tick species. This advancement reflects our unwavering commitment to help veterinarians protect dogs with the most comprehensive, convenient, and science‑driven solutions on the market,” Meg Conlon, DVM, executive director of US Companion Animal Veterinary Services at Merck Animal Health, said in a release.¹

Isoxazoline products are commonly used and safe for most dogs and cats, according to the FDA. However, the agency says that the products have been associated with neurologic adverse reactions such as muscle tremors, ataxia, and seizures in some dogs. Other adverse reactions observed in dogs and cats include lethargy, decreased appetite, vomiting, diarrhea, elevated liver enzymes, pruritus, lumps or swelling at the injection site, and a hypersensitivity reaction.^2,3

Pet owners are advised by the FDA to consult with a veterinarian to determine whether a product in the isoxazoline class is appropriate for their canine, and veterinarians should review a patient’s medical history before deciding on a drug therapy. Additionally, veterinary teams should advise dog owners about using fluralaner for extended-release injectable suspension in breeding dogs and define the appropriate treatment interval based on the species of ticks the dog is likely to encounter.^2-4

The new indication supports year-round protection from ticks. “Though people often think of flea and tick season during the summer months, studies have shown that while fleas and ticks are most active from early spring through the fall, they can be a threat year-round, especially knowing it only takes a few warm days for ticks to become active,” Frank Guerino, PhD, associate vice president of global pharmaceutical development at Merck Animal Health, said in a news release.^3-5 “With Bravecto Quantum, a single dose provides yearlong, continuous protection, simplifying care for both pet owners and veterinarians, and promoting [adherence].”

RELATED ARTICLE: First long-acting flea and tick treatment is FDA approved for dogs

References

1. FDA approves Bravecto Quantum (fluralaner for extended-release injectable suspension) from Merck Animal Health to treat and control Asian longhorned tick and Gulf Coast tick for 12 months in dogs. News release. Merck Animal Health. March 18, 2026. Accessed March 19, 2026. https://www.businesswire.com/news/home/20260318568281/en/FDA-Approves-BRAVECTO-QUANTUM-fluralaner-for-extended-release-injectable-suspension-from-Merck-Animal-Health-to-Treat-and-Control-Asian-Longhorned-Tick-and-Gulf-Coast-Tick-for-12-Months-in-Dogs
2. FDA approves first long-acting flea and tick treatment for dogs. FDA. July 10, 2025. Accessed March 19, 2026. https://www.fda.gov/animal-veterinary/cvm-updates/fda-approves-first-long-acting-flea-and-tick-treatment-dogs?utm_medium=email&utm_source=govdelivery
3. Crossley KC. First long-acting flea and tick treatment is FDA-approved for dogs. dvm360. Published July 10, 2025. Updated July 14, 2025. Accessed March 19, 2026. https://www.dvm360.com/view/first-long-acting-flea-and-tick-treatment-is-fda-approved-for-dogs
4. Freedom of information summary: new animal drug application: Bravecto Quantum. FDA. July 10, 2025. Accessed March 19, 2025. https://animaldrugsatfda.fda.gov/adafda/app/search/public/document/downloadFoi/17185
5. FDA approves Bravecto Quantum (fluralaner for extended-release injectable suspension) from Merck Animal Health. News release. Merck Animal Health. July 10, 2025. Accessed March 19, 2025. https://www.merck.com/news/fda-approves-bravecto-quantum-fluralaner-for-extended-release-injectable-suspension-from-merck-animal-health/