FDA expands Bravecto Quantum label for two more tick species

Merck Animal Health has secured an FDA label expansion for Bravecto Quantum in dogs, adding Asian longhorned tick and Gulf Coast tick to the product’s list of labeled targets for 12 months of treatment and control after a single injection. Merck announced the expanded indication on March 18, 2026. The move builds on the product’s original July 10, 2025 FDA approval, which made Bravecto Quantum the first FDA-approved flea and tick treatment for dogs with protection lasting 8 to 12 months, depending on the tick species involved. (merck-animal-health.com)

That original approval already positioned Bravecto Quantum differently from monthly or quarterly preventives because it must be prescribed by a licensed veterinarian and administered in clinic. FDA said that professional oversight is needed not only for injection and adverse-event monitoring, but also to determine the correct retreatment interval based on the species of ticks a dog is likely to encounter. In practice, that species-specific decision remains central to the product’s use. (fda.gov)

Under the updated label, Bravecto Quantum now covers fleas plus five tick species for 12 months: Asian longhorned tick, Gulf Coast tick, black-legged tick, American dog tick, and brown dog tick. Coverage against lone star tick still extends only 8 months, not a full year. That distinction has already drawn outside scrutiny. In a March 5, 2026 decision, BBB National Programs’ National Advertising Division said Merck had support for saying the product can protect dogs “year round,” but also said the FDA-approved labeling shows duration varies by tick species, with lone star tick protection limited to 8 months. (merck-animal-health.com)

The expanded indication also lands as veterinarians continue to track shifting tick ecology. USDA describes the Asian longhorned tick as an aggressive, invasive species that can create large infestations, while other public health and veterinary sources note its spread in the U.S. and its significance for livestock and companion animal surveillance. Gulf Coast tick carries its own veterinary relevance: extension and peer-reviewed sources describe it as a vector associated with canine hepatozoonosis and other pathogens, particularly in endemic areas. Taken together, the newly added species strengthen the product’s usefulness in parts of the country where tick exposure is becoming more complex. (aphis.usda.gov)

Merck has also pointed to supporting data presented in 2025 on the injectable formulation’s safety, efficacy, and onset. In those materials, the company said the most commonly reported adverse reactions in a U.S. field study included lethargy, decreased appetite, vomiting, diarrhea, elevated liver enzymes, and pruritus. Product labeling also lists post-approval reports from foreign markets, including gastrointestinal reactions, injection-site reactions, hypersensitivity reactions, and neurologic events such as seizures, ataxia, and tremors. Those reports don’t establish frequency in U.S. use, but they do reinforce the need for case selection, counseling, and post-administration monitoring. (merck-animal-health.com)

Why it matters: For veterinary teams, the bigger story is less about one new SKU and more about how parasite prevention is being reframed around compliance, geography, and clinic control. A long-acting injectable can reduce missed doses among pet parents, but it also shifts more responsibility to the practice to assess regional tick pressure, document likely species exposure, and explain why “one shot a year” is not universally accurate for every dog. In areas with meaningful lone star tick exposure, the 8-month interval remains a critical operational detail. (fda.gov)

The approval may be especially relevant for practices in regions seeing expansion of invasive or historically localized ticks. For those clinics, a broader label could simplify recommendations for some canine patients, while also giving veterinarians another way to talk with pet parents about changing parasite risk. At the same time, the product’s administration requirements, adverse-event considerations, and species-specific duration mean it fits best as a medically managed preventive, not a one-size-fits-all convenience play. That nuance is likely to shape both uptake and competitive messaging in the flea-and-tick category. (fda.gov)

What to watch: Next, watch for whether Merck releases additional field-use data or uptake metrics, how competitors respond in marketing and claims challenges, and whether veterinary practices in high-risk regions adopt more formal tick-species risk assessment to guide Bravecto Quantum retreatment timing. (bbbprograms.org)