Fluralaner is a broad-spectrum antiparasitic active ingredient used in veterinary medicine in pets and chickens against external parasites (fleas, ticks, lice, mites, etc.). It is not used against agricultural and household pests. It belongs to the chemical class of the isoxazolines.

Common name: FLURALANER

Type: veterinary medicine
Chemical class: ISOXAZOLINES


Estructura molecular del fluralaner






Type of action: Broad-spectrum, systemic ectoparasiticide: insecticide, tickicide
Main veterinary parasites controlled: fleas (Ctenocephalides felis), ticks (Amblyomma americanum, Dermacentor variabilis, Dermacentor reticulatus, Ixodes ricinusIxodes scapularis, Rhipicephalus sanguineus), red fowl mites (Dermanyssus gallinae).

Efficacy against a specific parasite depends on the delivery form and on the dose administered. 

Click here for general information on features and characteristics of PARASITICIDES.


Dosing recommendations for antiparasitics depend on national regulations. National regulatory authorities determine whether a product is approved for a given indication, i.e. use on a particular host at a specific dose and against a specific parasiteCheck the labels of the products available in your country for specific information on approved indications.

The table below indicates some usual dosing recommendations for fluralaner issued by manufacturers or documented in the scientific literature. They may not be approved in some countries.

Fluralaner is an insecticide and acaricide with systemic mode of action that belongs to the chemical class of the isoxazolines, a pesticide class  introduced in 2013. So far it is only available for oral (chewable tablets) and topical (spot-on) administration to dogs, for topical administration (spot-on) to cats, and for oral administration (additive for drinking water) to chickens. Fluralaner controls fleas, ticks and a few other external parasites. It is ineffective against any kind of parasitic worms.

Dosing recommendations for FLURALANER
Delivery Parasites Dose (against fluralaner-susceptible parasites)
Oral Fleas 25-56 mg/kg; up to 3 months protection
Oral Ticks 25-56 mg/kg; 8 weeks protection against Amblyomma americanum; ~12 weeks protection against Rhipicephalus sanguineus Dermacentor spp and Ixodes spp
Oral Generalized demodicosis 25-56 mg/kg; >99% control 28 after treatment; 100% after 56 days
Topical Fleas 25-56 mg/kg; up to 3 months protection
Topical Ticks 25-56 mg/kg; 8 weeks protection against Amblyomma americanum; ~12 weeks protection against Rhipicephalus sanguineus Dermacentor spp and Ixodes spp
Delivery Parasites Dose (against fluralaner-susceptible parasites)
Topical Fleas 40-95 mg/kg; up to 3 months protection
Topical Ticks 40-95 mg/kg; 8 weeks protection against Dermacentor variabilis; ~12 weeks protection against and Ixodes scapularis
Delivery Parasites Dose (against fluralaner-susceptible parasites)
Oral Red fowl mites 0.5 mg/kg, 2X with 1 week interval; >99% control

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Oral LD50, rat, acute*:  >2000 mg/kg
Dermal LD50, rat, acute*: >2000 mg/kg
* These values refer to the active ingredient. Toxicity has to be determined for each formulation as well. Formulations are usually significantly less toxic than the active ingredients.

MRL (maximum residue limit) set for animal tissues (e.g. beef, mutton pork or chicken): set for chicken meat and eggs.
Withholding periods: Depens on the country. In the EU: 14 days for chicken meat, NIL for eggs.

Target Animal Safety studies done on the oral chews approved for dogs indicate that such products are well tolerated by dogs at the therapeutic dose. Similar studies on the topical spot-on found that ~6% of the treated dogs showed vomiting, ~4% hair fall (alopecia), ~2.7% diarrhea and lethargy. Comparable studies found that among the treated cats ~7.6% showed vomiting, ~5.4% itching, ~4.9% diarrhea and hair fall (alopecia), ~3.6% decreased appetite, ~3.1% lethargy and ~2.2% scabs or ulcerated lesions.

Due to their recent introduction there is very little knowledge on tolerance in different dog breeds or in young, old or otherwise weak animals.

After oral administration, no chemical residues are expected to contaminate the hair-coat of dogs after treatment. Therefore, in contrast with products for external use (e.g. spot-ons) there is no risk of contamination of humans (particularly children) getting in close contact with treated animals.

In September 2018 the FDA of the USA has alerted pet owners and veterinarians about potential neurological adverse events following the use of products containing isoxazolines in dogs. In August 2021 The FDA has extended this alert to cats. Some treated animals have experienced adverse events such as muscle tremors, ataxia (lack of voluntary coordination of muscle movements), and seizures. This regards all products containing isoxazolines. Most treated animals will not show such adverse drug reactions, but some may be affected.

For additional information read the article on fluralaner safety in this site.

General information on the safety of veterinary antiparasitics is available in specific articles in this site (click to visit):


It is obvious that veterinary products are not intended for and should never be used on humans!!!


Year of introduction: 2013
Introduced by: MSD ANIMAL HEALTH (active ingredient first described by NISSAN)
Some original AH brands: BRAVECTO
Patent: VALID

Use in LIVESTOCK: So far only in chicken
Use in

Main delivery forms: 

Use in human medicine: No
Use in
public/domestic hygiene: No
Use in
agriculture: No
Generics available: 


  • In pets: No
  • In livestock: NO

Learn more about parasite resistance and how it develops.


Fluralaner is a representative of the isoxazolines, a new class of insecticides discovered in the 2000s. Several major products have been approved so far (not everywhere yet): BRAVECTO oral chews (only for dogs), BRAVECTO topical solution (for dogs and cats), and EXZOLT for chickens.

There is so far little information available on this active ingredient. It is similar to afoxolaner and sarolaner, two other isoxazolines introduced in the 2010s.

Fluralaner is available for oral or topical administration to dogs, for topical administration to cats, and for oral administration to chickens. It has a systemic mode of action. Ingested or topically administered fluralaner is rapidly absorbed into blood and distributed throughout the whole body of the treated animal. Blood-sucking parasites are killed during their blood meal.

But the systemic mode of action means also that for fleas and/or ticks to be killed, they have to bite the dog first and suck enough blood before the ingested active ingredient kills them. Whether killing is fast enough to prevent disease transmission is not yet known.

As other isoxazolines with insecticidal and tickicidal efficacy, fluralaner is a non-competitive GABA (gamma-aminobutyric acid) receptor antagonist, much more selective for GABA receptors in insects or ticks, than for those in mammals, including humans. It binds to chloride channels in nerve and muscle cells, which blocks the transmission of neuronal signals. Affected parasites are paralyzed and die.

Efficacy of fluralaner

The EU approvals indicate:

If the product really delivers, such a long lasting effect against fleas and ticks with a single tablet is rather unique and superior to most other flea and tick products currently available for dogs. However, there are several tick species that infect dogs in many regions and are not mentioned in the label: Amblyomma cajennense, Hyalomma spp, Haemaphysalis spp, etc. The future will show whether these other ticks are controled as well.

Studies in the literature suggest that a single treatment is also effective against canine demodicosis (Demodex canis). In laboratory studies fluralaner has also shown efficacy against mosquito larvae (Aedes aegypti), blowfly larvae (Lucilia cuprina), adult cattle ticks (Rhipicephalus microplus), and soft tick nymphs (Ornithodoros moubata) higher than fipronil.

Click here to view the list of all technical summaries of antiparasitic active ingredients in this site.<