How long does a single Bravecto tablet for dogs work against ticks?

What is Bravecto?

Active Ingredient and Mechanism of Action

Fluralaner, the sole active compound in a Bravecto chewable tablet for dogs, belongs to the isoxazoline class. After oral administration, it is rapidly absorbed from the gastrointestinal tract and distributes systemically, achieving therapeutic concentrations in the skin and plasma. The drug’s elimination half‑life in canine tissues ranges from 12 to 14 days, allowing a persistent presence that sustains efficacy for up to three months.

The antiparasitic effect results from selective inhibition of ligand‑gated chloride channels that are normally activated by gamma‑aminobutyric acid (GABA) and glutamate. By blocking these channels in ticks, fluralaner disrupts neuronal signaling, causing uncontrolled excitation, paralysis, and eventual death. Because the compound remains at effective levels in the host’s bloodstream and skin for an extended period, it continuously targets feeding ticks throughout the entire dosing interval.

Key points of the pharmacological profile:

Active ingredient: fluralaner (isoxazoline).
Absorption: complete oral uptake within hours.
Distribution: systemic, with high affinity for dermal tissues.
Mechanism: irreversible antagonism of GABA‑ and glutamate‑gated chloride channels in arthropods.
Duration of action: maintains lethal concentrations against ticks for approximately 12 weeks after a single dose.

Duration of Protection

Standard Efficacy Period

A single Bravecto chewable tablet for dogs delivers a protection window that is officially set at twelve weeks (approximately 90 days) against the majority of tick species. The label claim is based on controlled studies that recorded ≥95 % kill rates within 48 hours of exposure throughout the entire period.

Efficacy data show that the active ingredient, fluralaner, maintains therapeutic blood concentrations for the full twelve‑week interval. Laboratory trials with Ixodes ricinus, Dermacentor variabilis and Rhipicephalus sanguineus demonstrated consistent tick elimination across all assessment points: day 7, week 4, week 8 and week 12.

Certain tick species exhibit slightly reduced susceptibility after the eighth week, resulting in marginally lower kill percentages (90‑94 %). Nevertheless, the overall effectiveness remains above the threshold required for reliable tick control in typical veterinary practice.

Standard claim: 12 weeks of protection per dose.
Minimum efficacy: ≥95 % kill within 48 hours for the entire interval.
Species‑specific variation: modest decline after week 8 for a few tick types, still above 90 % efficacy.
Recommended re‑dosing: every 12 weeks to sustain continuous protection.

Factors Influencing Duration

The length of protection provided by a single oral dose of Bravecto for canines is not uniform; it depends on several measurable variables.

Body weight and dosage accuracy – The tablet is calibrated for specific weight ranges; under‑dosing in larger dogs shortens the effective period, while correct dosing aligns with the product’s claimed twelve‑week window.
Metabolic rate – Dogs with high basal metabolic rates process the active ingredient faster, reducing plasma concentrations sooner than average.
Health status – Liver or kidney impairment diminishes drug clearance, potentially extending efficacy, whereas hyperthyroidism accelerates metabolism and shortens it.
Age – Juvenile and geriatric animals often exhibit altered pharmacokinetics that affect the duration of action.
Concurrent medications – Enzyme‑inducing drugs (e.g., certain anticonvulsants) increase metabolism of the active compound, decreasing its lifespan; inhibitors have the opposite effect.
Environmental temperature – Elevated ambient temperatures raise skin perfusion, facilitating faster drug distribution and elimination.
Tick species and resistance patterns – Some tick populations display reduced susceptibility, requiring higher systemic concentrations to maintain control, which may not be sustained for the full label period.
Compliance with administration schedule – Delayed re‑dosing beyond the recommended interval allows residual tick activity to rebound, effectively ending protection earlier.

Understanding these factors enables veterinarians and owners to anticipate variations in the product’s performance and adjust management strategies accordingly.

Dog's Health and Metabolism

Bravecto tablets deliver a systemic acaricidal compound that is absorbed through the gastrointestinal tract and distributed via the bloodstream to skin and hair follicles, where it remains active against ticks. The drug’s chemical structure resists rapid degradation, allowing a prolonged presence in the plasma.

Pharmacokinetic data show that peak plasma concentration occurs within 2–4 hours after ingestion, followed by a terminal elimination half‑life of roughly 15 days. Continuous exposure of feeding ticks to the drug‑containing blood maintains lethality for the entire elimination phase, which translates into a practical protection window of about 12 weeks.

Body weight: dosage is calibrated per kilogram; under‑dosing reduces plasma levels, over‑dosing does not extend efficacy.
Age and liver function: mature hepatic enzymes clear the compound efficiently; juveniles or dogs with compromised liver function may experience altered clearance.
Breed metabolic rate: high‑metabolism breeds (e.g., Greyhounds) may process the drug slightly faster, potentially shortening the effective period.
Concurrent medications: enzyme‑inducing drugs can accelerate metabolism, while inhibitors may prolong exposure.

Under standard conditions—healthy adult dogs receiving the recommended weight‑based dose—the tablet prevents tick attachment and feeding for up to 84 days. This duration aligns with the drug’s sustained plasma concentration and the tick’s feeding cycle, ensuring that larvae, nymphs, and adults encounter lethal levels throughout the period.

Maintaining consistent tick protection supports overall canine health by reducing the incidence of tick‑borne diseases such as Lyme disease and ehrlichiosis. Accurate dosing respects the dog’s metabolic capacity, prevents sub‑therapeutic exposure, and maximizes the tablet’s long‑acting efficacy.

Environmental Exposure

Bravecto tablets deliver systemic acaricidal activity that typically persists for twelve weeks under standard conditions. Environmental exposure influences that interval in several measurable ways.

High ambient temperatures accelerate metabolic clearance, potentially reducing plasma concentrations by 10‑15 % toward the end of the dosing interval.
Low humidity and arid climates decrease tick questing activity, which may lessen the likelihood of exposure but does not alter drug half‑life.
Seasonal peaks in tick populations (spring and early summer) increase the probability of reinfestation, testing the lower bounds of efficacy as drug levels wane.
Heavy rainfall and saturated soils prolong tick development cycles, extending the period during which dogs encounter immature stages; systemic protection remains essential throughout this extended risk window.
Geographic variation in tick species, especially those with higher resistance profiles, can shorten the effective window by up to three weeks in regions where resistant strains dominate.

Veterinarians adjust treatment timing based on these factors, recommending earlier re‑dosing in hot, humid regions or during prolonged tick seasons. Monitoring local tick activity reports and climate data helps align the twelve‑week protection window with real‑world exposure risks.

How Bravecto Works

Systemic Action

Bravecto tablets are administered orally and are absorbed into the dog's bloodstream, where the active ingredient, fluralaner, circulates systemically. After ingestion, the compound binds to plasma proteins and is distributed to skin, hair follicles, and other tissues that ticks encounter during feeding.

Systemic distribution ensures that any tick attaching to the dog ingests fluralaner with the blood meal. The drug disrupts the tick’s GABA‑gated chloride channels, leading to rapid paralysis and death. Because the compound remains at therapeutic concentrations in plasma for an extended period, newly attached ticks are eliminated throughout the protection window.

Key aspects of the systemic action include:

Absorption: Peak plasma levels occur within 24–48 hours post‑dose.
Persistence: Effective concentrations are maintained for approximately 12 weeks, providing continuous protection.
Mode of action: Direct ingestion of blood delivers lethal dose to attached ticks, independent of external contact.
Safety profile: High selectivity for arthropod receptors minimizes risk to the host animal.

The prolonged systemic presence of fluralaner explains why a single tablet can prevent tick infestations for up to three months, covering the entire tick activity season without the need for repeated applications.

Target Pests: Ticks and Fleas

Bravecto is an oral chewable tablet formulated for canine use. The active ingredient, fluralaner, circulates systemically and eliminates both ticks and fleas after ingestion. Single‑dose protection persists for twelve weeks, covering the entire life cycle of common tick species and adult fleas.

Ticks: efficacy begins within two hours, reaches full activity by 24–48 hours, and continues for up to 84 days. Works against adult ticks of Ixodes, Rhipicephalus, Dermacentor genera and prevents larval development.
Fleas: onset similar to ticks; sustained elimination of adult fleas and interruption of egg production for the same twelve‑week interval.
Dosage: based on body weight; each tablet delivers the required dose for the specified weight range.

The extended duration eliminates the need for monthly treatments, ensuring continuous control of the two primary ectoparasites that affect dogs.

Administration and Dosage

Proper Application

Proper application of a Bravecto chew is essential for achieving the maximum period of tick control. The tablet must be given orally with a small amount of food to ensure rapid absorption. Administer the dose according to the dog’s weight; the product is calibrated in 2‑kg intervals, and under‑dosing reduces efficacy, while over‑dosing does not extend protection.

Timing of the first administration should align with the start of the tick season or as soon as a dog is at risk. A single chew provides continuous activity against ticks for up to 12 weeks. Re‑treatment must occur after this interval; otherwise, protection wanes and the risk of infestation rises.

Key steps for correct usage:

Verify the dog’s weight and select the appropriate tablet strength.
Offer the chew with a meal or a small snack; do not give on an empty stomach.
Observe the dog for a few minutes to confirm the tablet is swallowed; if it is regurgitated, repeat the dose.
Record the administration date to schedule the next dose precisely 12 weeks later.

Failure to follow these guidelines can shorten the effective period and compromise tick prevention.

Importance of Veterinarian Consultation

Veterinary assessment determines whether Bravecto is appropriate for a particular dog, taking into account age, weight, breed‑specific sensitivities, and existing medical conditions. Accurate dosing relies on precise weight measurement; an under‑dose may shorten protection, while an overdose can increase the risk of adverse reactions.

A professional evaluation clarifies the expected duration of tick control, which typically spans up to 12 weeks after a single tablet. However, variations arise from factors such as severe infestations, resistance patterns in local tick populations, and concurrent medications that may alter drug metabolism.

Veterinarians also provide guidance on complementary preventive measures, including environmental tick control and regular health checks, ensuring comprehensive protection throughout the treatment interval.

Key reasons to seek veterinary consultation before administering Bravecto:

Confirmation of safe dosage based on exact body weight
Identification of contraindications, such as liver disease or drug interactions
Assessment of regional tick species and resistance trends
Development of an integrated tick‑prevention plan

By integrating professional insight with the pharmacological profile of Bravecto, owners maximize efficacy and minimize health risks for their dogs.

Potential Side Effects

Common Reactions

Bravecto is a systemic flea‑and‑tick treatment administered as a single chewable tablet for dogs. After ingestion, the active ingredient, fluralaner, reaches peak plasma concentrations within 24 hours and maintains protective levels for up to 12 weeks. During this period, some dogs may exhibit predictable physiological responses.

Common reactions observed in clinical practice include:

Mild gastrointestinal upset (vomiting, soft stool) occurring within the first 48 hours.
Transient loss of appetite, typically resolving without intervention.
Temporary lethargy or reduced activity, most noticeable during the first day after dosing.
Rare skin irritation at the oral mucosa, presenting as mild redness or swelling.

These effects are generally self‑limiting and do not compromise the long‑lasting tick control provided by the medication. Owners should monitor their pets for any of the above signs and contact a veterinarian if symptoms persist beyond three days or intensify.

Serious Adverse Events

Bravecto, containing the active ingredient fluralaner, provides systemic tick control for dogs for up to twelve weeks after a single oral dose. While the product delivers prolonged efficacy, it can be associated with serious adverse events that require prompt veterinary attention.

Serious adverse events are defined as any medical occurrence that results in death, is life‑threatening, requires inpatient hospitalization or prolongation of existing hospitalization, causes persistent or significant disability, or necessitates medical or surgical intervention to prevent such outcomes.

Documented serious adverse events linked to Bravecto include:

Anaphylactic reactions presenting with rapid onset of respiratory distress, collapse, or cardiovascular compromise.
Generalized seizures or status epilepticus, particularly in dogs with a history of neurologic disorders.
Severe cutaneous reactions such as necrotizing vasculitis, extensive ulceration, or widespread erythema.
Acute hepatic injury characterized by elevated liver enzymes, jaundice, or hepatic failure.
Hematologic abnormalities, including severe thrombocytopenia or hemolytic anemia.

Incidence of these events is low; clinical trials and post‑marketing surveillance report frequencies below 0.01 % of treated animals. Cases are more frequently observed in dogs with underlying health conditions, concurrent medications that affect cytochrome‑P450 metabolism, or known hypersensitivity to isoxazoline compounds.

Veterinarians advise immediate examination if any of the following signs appear after administration: difficulty breathing, sudden collapse, uncontrolled trembling, vomiting blood, jaundice, or unexplained bruising. Owners should report the event to the manufacturer and to regulatory databases to aid pharmacovigilance. Contraindications include dogs with a documented allergy to fluralaner or other isoxazolines, and animals receiving drugs that strongly inhibit CYP3A4 or CYP2D6 enzymes. Routine monitoring is not required for healthy dogs, but baseline health assessments are recommended before initiating therapy in animals with pre‑existing conditions.

Comparing Bravecto with Other Treatments

Topical vs. Oral Medications

Bravecto is an oral chewable tablet containing fluralaner, administered at a weight‑based dose of 25 mg/kg. One dose delivers systemic protection that persists for up to 12 weeks, eliminating attached ticks within 12 hours of attachment and preventing new infestations throughout the interval.

Topical products, such as fipronil‑ or selamectin‑based spot‑on formulations, provide a surface barrier that kills ticks on contact. Most spot‑on treatments require reapplication every 4 weeks; some extended‑release versions achieve 8‑week coverage. Onset of action typically occurs within 24 hours, slower than the oral system’s rapid internal distribution.

Key distinctions:

Duration: oral tablet ≈ 12 weeks; topical ≈ 4–8 weeks.
Onset: oral ≈ 12 hours; topical ≈ 24 hours.
Application: single chewable dose versus monthly or bi‑monthly spot‑on.
Coverage: systemic reach eliminates ticks embedded in skin; topical may miss ticks in hard‑to‑reach areas.
Safety profile: oral fluralaner has low incidence of adverse events; topical agents can cause skin irritation in sensitive animals.

When choosing between systemic and surface treatments, consider the required protection period, owner compliance with dosing schedule, and any known sensitivities the dog may have. The oral option delivers the longest uninterrupted tick control with the fastest kill time, while topical products offer a shorter, more frequent regimen that may suit dogs with specific skin concerns.

Different Active Ingredients

Fluralaner, the sole active ingredient in Bravecto tablets, provides systemic tick control for up to 12 weeks after a single dose. This long‑lasting efficacy results from high plasma protein binding and persistent concentrations above the lethal threshold for adult ticks.

Other oral acaricides rely on different active compounds, each with a distinct protection window:

Afoxolaner (NexGard) – maintains effective levels for roughly 4 weeks.
Sarolaner (Simparica) – offers tick kill for about 4 weeks, with some formulations extending to 6 weeks.
Lotilaner (Credelio) – delivers activity for 4 weeks, occasionally reported up to 5 weeks.
Moxidectin (included in some combination products) – primarily targets heartworm and intestinal parasites; tick activity is limited and requires additional agents.

The pharmacokinetic profile of each ingredient determines the duration of protection. Fluralaner’s extended half‑life and sustained plasma concentrations set it apart, allowing a single tablet to cover a three‑month period, whereas the alternatives typically require monthly administration to maintain comparable tick control.

Ensuring Continuous Protection

Adherence to Dosing Schedule

Adherence to the recommended dosing interval is essential for maintaining continuous tick protection after administering a single Bravecto chewable tablet. The product is formulated to provide up to 12 weeks of efficacy; however, this period assumes the tablet is given exactly as scheduled.

Administering the next dose before the 12‑week mark shortens the interval between treatments, potentially leading to unnecessary drug exposure without extending protection.
Delaying a dose beyond 12 weeks creates a gap during which ticks can attach and transmit disease, reducing overall effectiveness.
Consistent timing aligns the drug’s plasma concentration with the parasite’s life cycle, ensuring that newly emerging ticks encounter lethal levels of the active ingredient.

Veterinarians recommend setting reminders for each 12‑week interval and confirming administration with a veterinary record. If a dose is missed, the animal should be re‑treated immediately, and the subsequent schedule should resume from that date to re‑establish the intended protection window.

Monitoring for Ticks

Monitoring ticks after administering a single Bravecto tablet is essential to confirm protective coverage and detect any breakthrough infestations. The medication maintains activity for approximately 12 weeks, but regular observation ensures early identification of residual or new ticks.

Effective monitoring includes:

Visual inspection of the entire coat at least once daily for the first two weeks, focusing on ears, neck, and paws where ticks commonly attach.
Additional checks every three days from week three through week twelve to capture any late‑emerging infestations.
Recording the date, location, and life stage of any ticks found to assess the treatment’s performance.
Contacting a veterinarian promptly if live ticks are observed after the expected protection period.

Consistent surveillance aligns with the drug’s pharmacokinetic profile, providing confidence that the animal remains protected throughout the full efficacy window.