MDose · Veterinary drug reference
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Source overview
Recorded excerpts for one species. Each dose remains a separate source entry; no regimen is selected.
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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
Heartworm prevention (FDA-approved); microfilaricide, slow-kill adulticide adjunct, demodicosis (higher doses)
DogExtra-label (EXTRA_LABEL)1 source record · View provenance
- Dog · Plumb's Veterinary Drug Handbook, 7th ed., p. 684–686; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 420–422 — Indications table · Not applicable · Extra-label (EXTRA_LABEL) · Pending clinical review (PROPOSED) · Rule-based
Original excerpt: Heartworm prevention (FDA-approved); microfilaricide, slow-kill adulticide adjunct, demodicosis (higher doses) — Labeled (heartworm prevention); other uses extra-label
- Dog · Plumb's Veterinary Drug Handbook, 7th ed., p. 684–686; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 420–422 — Indications table · Not applicable · Extra-label (EXTRA_LABEL) · Pending clinical review (PROPOSED) · Rule-based
Heartworm prevention (FDA-approved)
CatNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Cat · Plumb's Veterinary Drug Handbook, 7th ed., p. 684–686; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 420–422 — Indications table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Original excerpt: Heartworm prevention (FDA-approved) — Labeled
- Cat · Plumb's Veterinary Drug Handbook, 7th ed., p. 684–686; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 420–422 — Indications table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Dose regimens8
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 effects204
Shock-like reaction (microfilaricide use) — depression, hypothermia, vomiting — Uncommon, related to dying microfilariae
DogNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Dog · Plumb's Veterinary Drug Handbook, 7th ed., p. 684–686; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 420–422 — Side Effects / Adverse Effects table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Neurotoxicity: hypersalivation, depression, ataxia, blindness, coma — Dose- and breed-dependent
DogNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Dog · Plumb's Veterinary Drug Handbook, 7th ed., p. 684–686; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 420–422 — Side Effects / Adverse Effects table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Retinopathy (sudden blindness/mydriasis, usually reversible) — High-dose only
DogNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Dog · Plumb's Veterinary Drug Handbook, 7th ed., p. 684–686; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 420–422 — Side Effects / Adverse Effects table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Vomiting, ataxia, lethargy — Overdose
CatNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Cat · Plumb's Veterinary Drug Handbook, 7th ed., p. 684–686; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 420–422 — 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
- INEFFECTIVE, HEARTWORM LARVAE37,144 reports
- Lack of efficacy (endoparasite) - hookworm26,103 reports
- Lack of efficacy (endoparasite) - heartworm24,388 reports
- Vomiting22,793 reports
- Digestive tract disorder NOS16,656 reports
- INEFFECTIVE, ASCARIDS NOS11,819 reports
- Cardiac disorder NOS10,095 reports
- Diarrhoea9,722 reports
- Lack of efficacy - NOS8,746 reports
- INEFFECTIVE, HOOKS6,958 reports
- Lethargy (see also Central nervous system depression in 'Neurological')6,792 reports
- Lack of efficacy (endoparasite) - roundworm NOS5,058 reports
Cat
- Vomiting291 reports
- Ataxia255 reports
- Depression140 reports
- Mydriasis135 reports
- Accidental exposure96 reports
- Anorexia94 reports
- Death87 reports
- Trembling63 reports
- Diarrhoea59 reports
- Lethargy (see also Central nervous system depression in 'Neurological')59 reports
- Loss of consciousness52 reports
- Hypothermia48 reports
Monitoring1
Confirm heartworm-negative status before starting prophylaxis or microfilaricide use; observe for 4+ hours after high-dose administration in at-risk breeds (CNS signs can appear within 4h in sensitive dogs)
Species not recordedNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Species not recorded · Plumb's Veterinary Drug Handbook, 7th ed., p. 684–686; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 420–422 — Monitoring Parameters · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Contraindications1
Public-health/label restriction — not for use in lactating dairy animals; not recommended in puppies <6 weeks old
Species not recordedNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Species not recorded · Plumb's Veterinary Drug Handbook, 7th ed., p. 684–686; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 420–422 — Contraindications & Warnings table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Precautions4
ABCB1-1Δ (formerly MDR1) mutant breeds — Collies, Australian Shepherds, Shelties, Old English Sheepdogs, long-haired Whippets — at higher risk of CNS toxicity at doses above the heartworm-prevention range; genetic testing recommended before high-dose (e.g., demodicosis) use in these breeds
Species not recordedNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Species not recorded · Plumb's Veterinary Drug Handbook, 7th ed., p. 684–686; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 420–422 — Contraindications & Warnings table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Never substitute large-animal (cattle/horse) injectable ivermectin formulations for small-animal dosing without extremely careful dilution/calculation — this is a well-documented, sometimes fatal, dosing-error scenario.
Species not recordedNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Species not recorded · Plumb's Veterinary Drug Handbook, 7th ed., p. 684–686; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 420–422 — Clinical pearl · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
At the low heartworm-prevention dose, even ABCB1-mutant dogs are generally considered safe to treat — the major risk arises at the much higher off-label doses (e.g., demodicosis, aggressive microfilaricide protocols).
Species not recordedNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Species not recorded · Plumb's Veterinary Drug Handbook, 7th ed., p. 684–686; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 420–422 — Clinical pearl · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Combined with doxycycline pre-treatment (10 mg/kg BID × 4 weeks) as part of the "moxi/doxy" or slow-kill heartworm adulticide protocol per American Heartworm Society guidance.
Species not recordedNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Species not recorded · Plumb's Veterinary Drug Handbook, 7th ed., p. 684–686; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 420–422 — Clinical pearl · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Interactions3
P-glycoprotein inhibitors (ketoconazole, itraconazole, cyclosporine, diltiazem, verapamil, erythromycin, clarithromycin, spironolactone, amiodarone, quinidine, tamoxifen, carvedilol) — ↑ CNS penetration/toxicity risk, especially in ABCB1-mutant breeds — some sources state never combine ivermectin with ketoconazole in dogs
Species not recordedNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Species not recorded · Plumb's Veterinary Drug Handbook, 7th ed., p. 684–686; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 420–422 — Drug Interactions table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Benzodiazepines — Potentiated effects
Species not recordedNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Species not recorded · Plumb's Veterinary Drug Handbook, 7th ed., p. 684–686; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 420–422 — Drug Interactions table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Spinosad (Comfortis) — Avoid with high extra-label ivermectin doses
Species not recordedNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Species not recorded · Plumb's Veterinary Drug Handbook, 7th ed., p. 684–686; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 420–422 — Drug Interactions table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Pharmacokinetics5
Bioavailability — Up to 95% oral (simple-stomached animals)
DogCatNot applicable (NOT_APPLICABLE)2 source records · View provenance
- Dog · Plumb's Veterinary Drug Handbook, 7th ed., p. 684–686; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 420–422 — Pharmacokinetics table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
- Cat · Plumb's Veterinary Drug Handbook, 7th ed., p. 684–686; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 420–422 — Pharmacokinetics table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Volume of distribution — 2.4 L/kg (dog)
Other speciesNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Other species · Plumb's Veterinary Drug Handbook, 7th ed., p. 684–686; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 420–422 — Pharmacokinetics table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Half-life — ~2 days (dog, oral); 100–145h after SQ injection
Species not recordedNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Species not recorded · Plumb's Veterinary Drug Handbook, 7th ed., p. 684–686; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 420–422 — Pharmacokinetics table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Metabolism — Hepatic, oxidative
Other speciesNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Other species · Plumb's Veterinary Drug Handbook, 7th ed., p. 684–686; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 420–422 — Pharmacokinetics table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Pregnancy / lactation considerations1
Considered safe at labeled/prophylactic doses; reproductive studies in dogs/cattle/horses/swine show no adverse fetal effects at these doses. Human FDA category C. Papich class A. Excreted in milk at low levels — minimal risk to nursing offspring at standard doses.
Species not recordedNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Species not recorded · Plumb's Veterinary Drug Handbook, 7th ed., p. 684–686; Saunders Handbook of Veterinary Drugs (Papich), 4th ed., p. 420–422 — Pregnancy & Lactation · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Literature references11
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.
- Assessing the efficacy of high-dose rifampicin plus albendazole against onchocerciasis.
Study summary not available in the imported record. Open the original citation to review the study.
- In Vivo Acaricidal Effect of Linoleic Acid and Olive Oil Against Psoroptes cuniculi Mites in Experimentally Infested Rabbits.
Study summary not available in the imported record. Open the original citation to review the study.
- Drug Resistance Assessment of Commonly Used Anthelmintics, and Their Combination Effect in Naturally Infected Sheep: The Case of Kaffa Zone, Southwestern Ethiopia.
Study summary not available in the imported record. Open the original citation to review the study.
- Comparative toxicity of thiamethoxam and abamectin in red swamp crayfish: Bioaccumulation, oxidative stress, and gut microbiota in a rice-crayfish Co-culture system.
Study summary not available in the imported record. Open the original citation to review the study.
- Field evidence of multiple anthelmintic resistance in gastrointestinal nematodes of small ruminants in Punjab, India, with comparative evaluation of molecular diagnostic tools for benzimidazole resistance detection in Haemonchus contortus.
Study summary not available in the imported record. Open the original citation to review the study.
Sources: 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
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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.