Prescribing overview
Heartgard Plus prevents canine heartworm disease and treats specified intestinal worms. It does not kill adult heartworms; established infection requires separate treatment.
Key prescribing checks
- The label calls for heartworm testing before starting prevention and periodic retesting. Patients with an established infection need a clinician-directed plan.
- Confirm age eligibility and ensure the full chewable is actually consumed. Record missed or incomplete administration for veterinary guidance rather than treating protection as guaranteed.
- Review susceptibility concerns and other parasite products before prescribing. Safety at labeled preventive exposure does not justify use of unrelated concentrated formulations.
- Observe for gastrointestinal or neurologic adverse signs and prevent access to stored chewables.
Uses by species
Approval and evidence apply to the named product, species, route and indication. An extra-label use requires its own prescribing assessment; a human indication is not an animal approval.
Dogs
FDA-approved Heartgard Plus indicationsHeartworm prevention; labeled roundworms/hookworms
Roundworms: T. canis/T. leonina; hookworms: A. caninum/U. stenocephala/A. braziliense.
Use / indication source ↗Pharmacology & pharmacokinetics
Mechanism and clinical role
Ivermectin eliminates tissue-stage heartworm larvae; pyrantel provides intestinal worm coverage.
Absorption, distribution, metabolism and elimination
The reviewed combination label supplies no quantitative canine PK parameters.
SAFETY REFERENCE · PRODUCT & SPECIES SPECIFIC
Contraindications & cautions
Contraindications identify circumstances where the source says a product should not be used. Precautions call for assessment or monitoring. Interactions identify combinations to review. They are distinct categories; this summary does not replace a full interaction check or the current product label.
Heartgard Plus
U.S. canine oral-chewable label.
Contraindications · when not to use
- No formal contraindications section is supplied; this does not establish unrestricted use.
Precautions & monitoring
- Test for heartworm first; existing infection needs a directed treatment plan. Review minimum age and choking/obstruction risk.
Safety sources checked: . Selected label information; independent veterinary or veterinary-pharmacy review remains pending. A label for dogs, cats, horses or humans does not establish safety for another species.
Adverse effects
Gastrointestinal and neurologic events are reported; chewing reduces choking/obstruction risk.
These are selected source-reported effects, not incidence estimates or an exhaustive list. Spontaneous postmarketing reports do not by themselves establish frequency or causality.
Dosing & administration
| Species & indication | Labeled regimen | Eligibility & source |
|---|---|---|
| Dogs ≥6 weeksHeartworm prevention and labeled intestinal wormsHeartgard Plus chewables | Minimum ivermectin 6 micrograms/kg + pyrantel 5 mg/kg (as pamoate) Oral · Monthly First dose within 30 days after first mosquito exposure; last within 30 days after last exposure | One chew: ≤25 lb:68 micrograms/57 mg; 26–50 lb:136 micrograms/114 mg; 51–100 lb:272 micrograms/227 mg (ivermectin/pyrantel). Above 100 lb use combinations. Verify full dosing label ↗ |
Weight-band ivermectin quantities are micrograms; pyrantel quantities are mg.
Extra-label prescribing and food-animal residue requirements are separate from labeled regimens. FDA extra-label-use guidance ↗
Drug & supplement interactions
This is a selected interaction reference, not an automated or comprehensive combination checker. Reconcile prescription drugs, nonprescription products, supplements and recent treatment changes.
A product-specific interaction summary has not been established here. An empty list must not be interpreted as “no interactions.” Review the full source and a species-appropriate clinical reference.
Monitoring
Test for existing heartworm infection before starting.
Client counseling
Encourage chewing; confirm entire dose consumed; contact veterinarian about rejected doses.
This section supports the veterinary team's discharge discussion; it does not replace the product’s Client Information Sheet where one is required.
Storage & handling
20–25°C; excursions15–30°C; protect from light.
Brands, formulations & ingredient identity
Active ingredients
ivermectin · pyrantel pamoate
Other searchable names: ivermectin pyrantel pamoate
Heartgard Plus contains ivermectin and pyrantel supplied as the pamoate salt. The Plus suffix is part of the product identity, not an optional branding detail.
Do not infer that every ivermectin product shares this combination, concentration, species label or route. Livestock and other concentrated ivermectin products are distinct.
Weight-range packaging is used for this chewable. Reconcile current weight, complete product name and package strength when checking the prescription.
Shared ingredients do not establish interchangeable concentrations, routes, release properties, species labeling or regional availability.
Heartgard Plus
- Formulation
- Oral chewables
- Label / product scope
- Dogs
Ivermectin plus pyrantel; canine preventive combination.
Product label / source ↗References & review status
Clinical reference updated October 16, 2026. Independent veterinary or veterinary-pharmacy review not yet completed. Evidence gaps remain explicitly identified; this page does not claim equivalence to a comprehensive, professionally reviewed veterinary formulary.
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