MDose · Veterinary drug reference
FENBENDAZOLE
Favorites and recent references stay on this device. No patient data is stored.
Choose the species
One selection filters the source overview, clinical facts, reports and dose calculator. Literature references are not species-filtered.
Choose one species for its overview and dose calculator, or all species to browse the full evidence.
Source overview
Recorded excerpts for one species. Each dose remains a separate source entry; no regimen is selected.
Choose one species to view its source overview. All-species evidence remains available below.
View full clinical evidence and sources ↓Clinical evidence
Pending clinical review (PROPOSED)Rule-based (RULE_BASED)— applies to the facts and dose entries in this species selection; individual source records retain their own status.
Indications2
Ascarids, hookworms, whipworms, Taenia tapeworms (labeled); Giardia, lungworms, Paragonimus (extra-label)
DogExtra-label (EXTRA_LABEL)1 source record · View provenance
- Dog · Plumb's Veterinary Drug Handbook, 7th ed., p. 509–512; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 343–344 — Indications table · Not applicable · Extra-label (EXTRA_LABEL) · Pending clinical review (PROPOSED) · Rule-based
Original excerpt: Ascarids, hookworms, whipworms, Taenia tapeworms (labeled); Giardia, lungworms, Paragonimus (extra-label) — Labeled (core parasites); extra-label for Giardia/lungworms
- Dog · Plumb's Veterinary Drug Handbook, 7th ed., p. 509–512; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 343–344 — Indications table · Not applicable · Extra-label (EXTRA_LABEL) · Pending clinical review (PROPOSED) · Rule-based
Ascarids, hookworms, Strongyloides, Taenia (extra-label — not FDA-approved in cats but considered safe/effective); Giardia, lungworms
CatExtra-label (EXTRA_LABEL)1 source record · View provenance
- Cat · Plumb's Veterinary Drug Handbook, 7th ed., p. 509–512; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 343–344 — Indications table · Not applicable · Extra-label (EXTRA_LABEL) · Pending clinical review (PROPOSED) · Rule-based
Original excerpt: Ascarids, hookworms, Strongyloides, Taenia (extra-label — not FDA-approved in cats but considered safe/effective); Giardia, lungworms — Extra-label
- Cat · Plumb's Veterinary Drug Handbook, 7th ed., p. 509–512; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 343–344 — Indications table · Not applicable · Extra-label (EXTRA_LABEL) · Pending clinical review (PROPOSED) · Rule-based
Dose regimens6
This calculator performs arithmetic only on the sourced dosing field shown for each result — it does not verify the field's accuracy, does not select which field to use for a patient, and does not replace a veterinarian's order. Not for clinical use. Confirm every result against the primary source before dispensing.
Choose one species above to view its dose calculator.
Adverse effects206
Generally very well tolerated, good safety margin — —
DogCatNot applicable (NOT_APPLICABLE)2 source records · View provenance
- Dog · Plumb's Veterinary Drug Handbook, 7th ed., p. 509–512; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 343–344 — Side Effects / Adverse Effects table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
- Cat · Plumb's Veterinary Drug Handbook, 7th ed., p. 509–512; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 343–344 — Side Effects / Adverse Effects table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Salivation, vomiting, diarrhea — Infrequent
DogCatNot applicable (NOT_APPLICABLE)2 source records · View provenance
- Dog · Plumb's Veterinary Drug Handbook, 7th ed., p. 509–512; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 343–344 — Side Effects / Adverse Effects table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
- Cat · Plumb's Veterinary Drug Handbook, 7th ed., p. 509–512; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 343–344 — Side Effects / Adverse Effects table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Hypersensitivity reaction (antigen release from dying parasites) — Possible, esp. high dosages
Other speciesNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Other species · Plumb's Veterinary Drug Handbook, 7th ed., p. 509–512; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 343–344 — Side Effects / Adverse Effects table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Pancytopenia — Rare, isolated case report
DogNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Dog · Plumb's Veterinary Drug Handbook, 7th ed., p. 509–512; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 343–344 — Side Effects / Adverse Effects table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
These are counts of spontaneously reported events, not proven adverse effects, causal relationships, or incidence rates.
Bars compare report counts within each species; they do not show incidence.
More reportsFewer reportsDog
- Vomiting1,115 reports
- Diarrhoea583 reports
- Depression497 reports
- Anorexia493 reports
- Lack of efficacy (endoparasite) - hookworm309 reports
- Death236 reports
- Lack of efficacy (endoparasite) - tapeworm139 reports
- INEFFECTIVE, HOOKS132 reports
- Other abnormal test result NOS128 reports
- Lethargy (see also Central nervous system depression in 'Neurological')116 reports
- Bloody diarrhoea102 reports
- Death by euthanasia94 reports
Cat
- Vomiting35 reports
- Death21 reports
- Diarrhoea18 reports
- Lethargy (see also Central nervous system depression in 'Neurological')14 reports
- Anorexia12 reports
- Ataxia12 reports
- Weight loss11 reports
- Accidental exposure10 reports
- Decreased appetite10 reports
- Hypersalivation10 reports
- Abnormal radiograph finding9 reports
- Death by euthanasia9 reports
Monitoring1
Fecal exam to confirm parasitological clearance, especially for Giardia (may need extended 5–7 day course if initial 3-day course fails)
Species not recordedNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Species not recorded · Plumb's Veterinary Drug Handbook, 7th ed., p. 509–512; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 343–344 — Monitoring Parameters · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Contraindications1
None specific — considered safe in all ages including neonates
Species not recordedNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Species not recorded · Plumb's Veterinary Drug Handbook, 7th ed., p. 509–512; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 343–344 — Contraindications & Warnings table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Precautions6
Single doses are NOT effective in dogs/cats — must treat ≥3 consecutive days for efficacy
Species not recordedNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Species not recorded · Plumb's Veterinary Drug Handbook, 7th ed., p. 509–512; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 343–344 — Contraindications & Warnings table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Single-dose treatment does not work — this is the most common practical dosing error; always counsel owners on completing the full 3-day (or longer) course.
Species not recordedNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Species not recorded · Plumb's Veterinary Drug Handbook, 7th ed., p. 509–512; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 343–344 — Clinical pearl · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
One of the safest anthelmintics available — appropriate first-line choice in pregnant/nursing animals and very young puppies/kittens.
Species not recordedNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Species not recorded · Plumb's Veterinary Drug Handbook, 7th ed., p. 509–512; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 343–344 — Clinical pearl · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Not effective against Dipylidium caninum (flea tapeworm) — use praziquantel for that indication instead.
Species not recordedNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Species not recorded · Plumb's Veterinary Drug Handbook, 7th ed., p. 509–512; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 343–344 — Clinical pearl · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
WARNINGS: http://www.fda.gov/reportanimalae NOT FOR USE IN HUMANS. KEEP OUT OF REACH OF CHILDREN. The Safety Data Sheet (SDS) contains more detailed occupational safety information. For customer service, adverse effects reporting, and/or a copy of the SDS, call 1-800-211-3573. For additional information about adverse drug experience reporting for animal drugs, contact FDA at 1-888-FDAVETS,.
Species not recordedOn-label (ON_LABEL)United States1 source record · View provenance
- Species not recorded · SPL section 34071-1 (WARNINGS SECTION) · United States · On-label (ON_LABEL) · Pending clinical review (PROPOSED) · Rule-based
Interactions1
Bromsalan flukicides (not available in US) — Do not combine — reported abortions in cattle, death in sheep with concurrent use
Species not recordedNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Species not recorded · Plumb's Veterinary Drug Handbook, 7th ed., p. 509–512; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 343–344 — Drug Interactions table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Pharmacokinetics3
Bioavailability — Marginal/poorly absorbed — this is expected, as action is largely local in the GI lumen
Other speciesNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Other species · Plumb's Veterinary Drug Handbook, 7th ed., p. 509–512; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 343–344 — Pharmacokinetics table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Metabolism — Interconverts with active metabolite oxfendazole (sulfoxide) and sulfone
Species not recordedNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Species not recorded · Plumb's Veterinary Drug Handbook, 7th ed., p. 509–512; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 343–344 — Pharmacokinetics table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Elimination — 44–50% unchanged in feces (ruminant data); <1% urine
Species not recordedNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Species not recorded · Plumb's Veterinary Drug Handbook, 7th ed., p. 509–512; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 343–344 — Pharmacokinetics table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Pregnancy / lactation considerations1
Considered safe in pregnancy for all species — drug of choice for treating Giardia in pregnant animals. Papich class A (probably safe).
Species not recordedNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Species not recorded · Plumb's Veterinary Drug Handbook, 7th ed., p. 509–512; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 343–344 — Pregnancy & Lactation · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Literature references19
References are linked to this drug. Species applicability is not recorded here, so the species filter does not narrow this list. Imported dates do not retain their original precision; confirm dates in the original citation.
- Morphomolecular characterization and statistical assessment of environmental associations with Diplectanum infestation in cultured European sea bass and bath treatment efficacy.
Study summary not available in the imported record. Open the original citation to review the study.
- Three-year evaluation of anthelmintic treatment efficacy against equine strongyles in France using FECRT.
Study summary not available in the imported record. Open the original citation to review the study.
- Targeted selective treatment against gastrointestinal nematodes in goats under Mozambican conditions.
Study summary not available in the imported record. Open the original citation to review the study.
- First Molecular Characterization of Aelurostrongylus abstrusus in a Naturally Infected Domestic Cat in Belgrade, Serbia: In-Depth Clinical, Radiological and Parasitological Findings.
Study summary not available in the imported record. Open the original citation to review the study.
- Effects of anthelmintics and gastrointestinal nematode infection intensity on growth and production performance and carcass quality in western Canadian feedlot cattle.
Study summary not available in the imported record. Open the original citation to review the study.
Sources: DailyMed, U.S. National Library of Medicine; PubMed, National Library of Medicine; openFDA, U.S. Food and Drug Administration; Plumb DC. Plumb's Veterinary Drug Handbook. 7th ed. PharmaVet Inc; 2011.
Owner information handout
Plain-language medication information to review with the owner. Open the handout to print it or download a PDF.
Available products
Products listed in the Health Canada Drug Product Database for this active ingredient. A listing does not establish that a product is authorized for the clinical uses described on this page.