Rafoxanide is an antiparasitic active ingredient used in veterinary medicine against internal parasites (e.g. some roundworm species and liver flukes) of livestock. It is not used against agricultural and household pests. It belongs to the chemical class of the salicylanilides.

Common name: RAFOXANIDE

Type: veterinary medecine
Chemical class: salicylanilide


Molecular structure of RAFOXANIDE 


Type of action: Anthelmintic endoparasiticide
Main veterinary parasites controlled: liver flukes, certain gastrointestinal roundworms (e.g. Haemonchus, Bunostomum, OesophagostomumChabertia)

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

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Rafoxanide is a narrow-spectrum anthelmintic effective against a few roundworms (mainly blood-sucking species) and against flukes (e.g. Fasciola hepatica). It is also effective against certain myiasis. It is not effective against tapeworms or external parasites. It is used scarcely in ruminants both as an injectable or a drench, often mixed with other anthelmintics. It is not used in swine, poultry, horses or pets.

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

Dosing recommendations for RAFOXANIDE
Delivery Parasites Dose (against rafoxanide-susceptible parasites)
Oral Gastrointestinal roundworms 7.5-10 mg/kg
Oral Fasciola hepatica 7.5-10 mg/kg
Subcutaneous Gastrointestinal roundworms 3 mg/kg
Subcutaneous Fasciola hepatica 3 mg/kg
Delivery Parasites  Dose (against rafoxanide-susceptible parasites)
Oral Gastrointestinal roundworms 7.5-10 mg/kg
Oral Oestrus ovis 7.5-10 mg/kg
Oral Fasciola hepatica 7.5-10 mg/kg
Delivery Parasites Dose (against rafoxanide-susceptible parasites)
Oral Fasciola hepatica 7.5 mg-kg

DISCLAIMER: Liability is denied for any possible damage or harm to persons, animals or any other goods that could follow the transmission or use of the information, data or recommendations in this site by any site visitor or third parties.

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 parasite. Check the labels of the products available in your country for specific information on approved indications.


Oral LD50, rat, acute*: >2000 mg/kg
Dermal LD50, rat, acute*: not found
* 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) established for either beef, mutton pork or chicken meat*:

  • CODEX: No
  • EU: Yes
  • USA: No
  • AUS: No

* This information is an indicator of the acceptance of an active ingredient by the most influential regulatory bodies for use on livestock.

Withholding periods for meat, milk, eggs, etc. depend on delivery form, dose and national regulations. Check the product label in your country.

Learn more about rafoxanide safety (poisoning, intoxication, overdose, antidote, symptoms, etc.).

General safety information for antiparasitics is available in specific articles in this site (click to visit):


Never use products for livestock on dogs and cats, unless they are explicitly approved for both livestock and pets. Pets may not tolerate livestock formulations.

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


Decade of introduction: 1970
Introduced by: Merck, Sharp & Dohme (MS&D) → MERIAL
Some original brands: FLUKANIDE, RANIDE
Patent: Expired (particular formulations may be still patent-protected)

Use in LIVESTOCK: Yes, rather scarce
Use in DOGS and CATS: No

Main delivery forms: 

Use in human medicine: No
Use in public/domestic hygiene: No
Use in agriculture: No
Generics available:  Yes, a few


In livestock: Yes, a few reports for Haemonchus worms.

Visit also the section in this site about parasite resistance to antiparasitics and more specifically to salicylanilides.


Rafoxanide is a veteran, narrow-spectrum flukicide and nematicide. It is still used in livestock, mainly in ruminants, but has been vastly replaced by more effective compounds. It is available in the form of injectables and drenches, often in combination with a broad-spectrum nematicide (e.g. benzimidazoles, macrocyclic lactones, levamisole)

rafoxanide is not used in dogs and cats.

Efficacy of rafoxanide

Rafoxanide is highly effective against adult and immature (older than 6 weeks) liver flukes (Fasciola hepatica and Fasciola gigantica), against a few gastrointestinal nematodes such as Haemonchus spp and Bunostomum spp, and also against nasal myiases caused by the sheep bot fly (Oestrus ovis).

Rafoxanide is not effective against numerous other gastrointestinal roundworms, lungworms (e.g. Dictyocaulus spp) eyeworms (e.g. Thelazia spp) or tapeworms.

Unlike many other anthelmintics (e.g. imidazothiazoles, benzimidazoles, tetrahydropyrimidines), rafoxanide has a residual effect, i.e. it not only kills the parasites present in the host at the time of treatment, but protects against re-infestation for a period of time (up to several weeks) that depends on the dose and the specific parasite.

Pharmacokinetics of rafoxanide

After oral administration rafoxanide is slowly absorbed into the bloodstream. Maximum blood concentrations are reached 2 to 3 days after treatment. Rafoxanide binds to >99% to plasma proteins. It is well distributed throughout the whole body but has a particular affinity for the thyroid gland.

Excretion is rather slow, mainly through bile and feces, mostly as unchanged parent molecule. Less than 1% of the administered dose was found in urine. Excretion half-life is about 10 days. Rafoxanide remains detectable in blood for more than 100 days after treatment.

Mechanism of action of rafoxanide

The molecular mode of action of salicylanilides, including rafoxanide, is not completely elucidated. They all are uncouplers of the oxidative phosphorylation in the cell mitochondria, which disturbs the production of ATP, the cellular "fuel". This seems to occur through suppression of the activity of succinate dehydrogenase and fumarate reductase, two enzymes involved in this process. This impairs the parasites motility and probably other processes as well.

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