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Roxee Meds Catalog

Spinosad

Medication catalog facts with explicit FDA-approval, off-label, source-limited, and safety context.

Both Catalog complete FDA data linked Rx required Tablet (Chewable) Elanco US Inc. Official label facts Owner quick guide first
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Data freshness

Storefront facts
Catalog refreshed
May 5, 2026, 10:00 a.m.

These are the storefront facts Roxee uses on browse cards and quick facts.

FDA applications
FDA application data refreshed
May 5, 2026, 10:00 a.m.

Sponsor, product, and application records imported from Animal Drugs @ FDA.

Safety reports
Safety data refreshed
May 5, 2026, 10:01 a.m.

openFDA reaction terms and case summaries are supporting evidence, not proof of causality.

Source timing details
Source timing details
  • Storefront facts: Source Roxee | Refreshed May 5, 2026, 10:00 AM UTC
    The storefront fact projection used for browse cards and quick facts.
  • Animal Drugs @ FDA: Source FDA | Refreshed May 5, 2026, 10:00 AM UTC
    Applications/products are imported from FDA export data.
  • Animal Drugs @ FDA previews: Source FDA | Refreshed Feb 9, 2026, 3:05 AM UTC
    Label highlights/doc links are fetched from FDA preview endpoints.
  • Animal Drug Product Listing Directory (NDC): Source FDA | Refreshed May 5, 2026, 10:00 AM UTC
    Package/product NDCs from FDA’s electronic listing directory (XLS).
  • openFDA reaction terms: Source FDA openFDA | Refreshed May 5, 2026, 10:04 AM UTC
  • openFDA case summaries: Source FDA openFDA | Refreshed May 5, 2026, 10:04 AM UTC

Evidence

Reviewed / Updated / Sources

Reviewed by: Not available

Last reviewed: February 12, 2026

Updated: February 12, 2026, 10:44 PM UTC

Sources:
Image coming soon
Spinosad

Spinosad

Drug type: Generic ingredient • Branded profile • FDA branded products available

Both Tablet (Chewable) Rx required 100% storefront ready

Species: Both

Manufacturer: Elanco US Inc.

Medication Snapshot

Merged from the current Roxee medication system with field-level provenance, freshness, and completeness tracking.

Spinosad

To kill fleas and for the prevention and treatment of flea infestations ( Ctenocephalides felis ) for 1 month on dogs and puppies 14 weeks of age and older and 5.0 pounds or body weight or greater. To kill fleas and for the prevention and treatment of flea infestations ( Ctenocephalides felis ) for 1 month on cats and kittens 14 weeks of age and older and 4.1 pounds of body weight or greater. Trifexis™ Chewable Tablets kill fleas and are indicated for the prevention and treatment of flea infestations ( Ctenocephalides felis ), and the treatment and control of adult hookworm ( Ancylostoma caninum ), adult roundworm ( Toxocara canis and Toxascaris leonina ) and adult whipworm ( Trichuris vulpis ) infections in dogs and puppies 8 weeks of age or older and 5 pounds of body weight or greater. Species commonly shown: Both, Dog, No Use Class Stated Or Implied, Cat, No Use Class Stated Or Implied.

Generic name
Spinosad
Brand names
Comfortis®, Comfortis
Manufacturer
Elanco US Inc.
Species
Both, Dog, No Use Class Stated Or Implied, Cat, No Use Class Stated Or Implied
Dosage forms
Tablet (Chewable)
Prescription
Prescription required
Completeness
100%
Validation
Complete
Brand names
Comfortis® Comfortis
Dosage forms
Tablet (Chewable)

Indications / Uses

To kill fleas and for the prevention and treatment of flea infestations ( Ctenocephalides felis ) for 1 month on dogs and puppies 14 weeks of age and older and 5.0 pounds or body weight or greater. To kill fleas and for the prevention and treatment of flea infestations ( Ctenocephalides felis ) for 1 month on cats and kittens 14 weeks of age and older and 4.1 pounds of body weight or greater. Trifexis™ Chewable Tablets kill fleas and are indicated for the prevention and treatment of flea infestations ( Ctenocephalides felis ), and the treatment and control of adult hookworm ( Ancylostoma caninum ), adult roundworm ( Toxocara canis and Toxascaris leonina ) and adult whipworm ( Trichuris vulpis ) infections in dogs and puppies 8 weeks of age or older and 5 pounds of body weight or greater.

Warnings / Contraindications

Federal law restricts this drug to use by or on the order of a licensed veterinarian. Federal (USA) law restricts this drug to use by or on the order of a licensed veterinarian. Treatment with fewer than 3 monthly doses after the last exposure to mosquitos may not provide complete heartworm prevention. Use with caution in breeding females. The safe use of TRIFEXIS in breeding males has not been evaluated. Use with caution in dogs with pre-existing epilepsy.

  • Federal law restricts this drug to use by or on the order of a licensed veterinarian. Federal (USA) law restricts this drug to use by or on the order of a licensed veterinarian. Treatment with fewer than 3 monthly doses after the last exposure to mosquitos may not provide complete heartworm prevention. Use with caution in breeding females. The safe use of TRIFEXIS in breeding males has not been evaluated. Use with caution in dogs with pre-existing epilepsy.

Side Effects

Top reported reactions (openFDA): Vomiting, Lethargy (see also Central nervous system depression in 'Neurological'), Lack of efficacy (endoparasite) - heartworm, Lack of efficacy (ectoparasite) - flea, Diarrhoea, Lack of efficacy (flea).

FAQ

Both, Dog, No Use Class Stated Or Implied, Cat, No Use Class Stated Or Implied

Yes. Roxee shows this as prescription-only.

Tablet (Chewable)

Related Medications

Afoxolaner Same category: Flea & Tick Doxycycline Same category: Flea & Tick Fluralaner 13.64% 12-Week Chew Same category: Flea & Tick Fluralaner Chew Tablets Same category: Flea & Tick Fluralaner Spot-On Solution Same category: Flea & Tick Imidacloprid Same category: Flea & Tick

Related Conditions

Fleas (Flea Infestation)

Source Transparency

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Pet Owner Quick Guide

Start here first for the safest next-step summary before the deeper medication detail.

Used for:

To kill fleas and for the prevention and treatment of flea infestations ( Ctenocephalides felis ) for 1 month on dogs and puppies 14 weeks of age and older and 5.0 pounds or body weight or greater.

Dosing note:

Exact dosing depends on your pet's species, weight, and health status. Use your veterinarian's instructions for the exact dose and schedule.

What to watch for:

  • Federal (USA) law restricts this drug to use by or on the order of a licensed veterinarian
  • Treatment with fewer than 3 monthly doses after the last exposure to mosquitos may not provide complete heartworm prevention
  • Use with caution in breeding females
  • The safe use of TRIFEXIS in breeding males has not been evaluated
  • Use with caution in dogs with pre-existing epilepsy
  • Skin scab (1 reports)
  • Seizure NOS (1 reports)
  • Generalised itching (1 reports)

When to call the vet:

  • Repeated vomiting or diarrhea.
  • Severe lethargy (hard to wake, very low energy).
  • Collapse or fainting.
  • Trouble breathing.
  • Facial swelling or hives.
  • Blood in vomit or stool.

Regulatory restrictions are shown in Vet View.

What to tell or ask your vet today:

  • Is this medicine the right fit for my pet’s current symptoms?
  • Which warning signs mean I should call back right away?
  • How should I handle missed doses or refusal to take the medicine?
Major cautions & emergency warning signs

Side effects to monitor:

  • Federal (USA) law restricts this drug to use by or on the order of a licensed veterinarian
  • Treatment with fewer than 3 monthly doses after the last exposure to mosquitos may not provide complete heartworm prevention
  • Use with caution in breeding females
  • The safe use of TRIFEXIS in breeding males has not been evaluated
  • Use with caution in dogs with pre-existing epilepsy

Most reported reactions:

  • Skin scab (1 reports)
  • Seizure NOS (1 reports)
  • Generalised itching (1 reports)

Emergency warning signs:

  • Repeated vomiting or diarrhea.
  • Severe lethargy (hard to wake, very low energy).
  • Collapse or fainting.
  • Trouble breathing.
Talk to a Vet / Find a Vet Near You Start Symptom Intake

Quick Facts

Official label facts first, then secondary summaries. Marketing content is separated below.

Species: Both
Manufacturer: Elanco US Inc.
Form: Tablet (Chewable)
Identifiers:
NADA: 141277 NADA: 141321 NDC Package: 58198-0042-1 NDC Package: 58198-0042-6 NDC Package: 58198-0043-1 NDC Package: 58198-0043-6 NDC Package: 58198-0044-1 NDC Package: 58198-0044-6 NDC Package: 58198-0045-1 NDC Package: 58198-0045-6 NDC Package: 58198-0046-1 NDC Package: 58198-0046-6 NDC Package: 58198-0071-1 NDC Package: 58198-0071-2 NDC Package: 58198-0072-1 NDC Package: 58198-0072-2 NDC Package: 58198-0073-1 NDC Package: 58198-0073-2 NDC Package: 58198-0074-1 NDC Package: 58198-0074-2
Source metadata:

Warnings / Contraindications

Federal law restricts this drug to use by or on the order of a licensed veterinarian. Federal (USA) law restricts this drug to use by or on the order of a licensed veterinarian. Treatment with fewer than 3 monthly doses after the last exposure to mosquitos may not provide complete heartworm prevention. Use with caution in breeding females. The safe use of TRIFEXIS in breeding males has not been evaluated. Use with caution in dogs with pre-existing epilepsy.

  • High: Federal law restricts this drug to use by or on the order of a licensed veterinarian. Federal (USA) law restricts this drug to use by or on the order of a licensed veterinarian. Treatment with fewer than 3 monthly doses after the last exposure to mosquitos may not provide complete heartworm prevention. Use with caution in breeding females. The safe use of TRIFEXIS in breeding males has not been evaluated. Use with caution in dogs with pre-existing epilepsy.
Source metadata:

Adverse Reactions

Snapshot first, detailed rows second. This section summarizes signal data and is not a diagnosis.

Tap or hover a reaction to see what it means in plain language.

Tracked signals
28
Reported cases
26
Serious reports
5
Species represented
2
Grouped by Body System
Digestive (1) · Vomiting Skin & allergy (4) · Itching, Generalised itching, Chewing - pruritus Neurologic (2) · Tiredness (lethargy), Seizure NOS Behavior (1) · Behavioral disorder (unspecified) Effectiveness (2) · Lack of efficacy (endoparasite) - heartworm, Lack of efficacy (ectoparasite) - flea Other (18) · Weight loss, UNPALATABLE, Tongue protrusion
Most Reported Reactions
Reaction Body system Cases Species Serious cases
Other 1 Dog 1
Neurologic 1 Dog 1
Skin & allergy 1 Dog 1
Other 1 Dog 1
Skin & allergy 1 Dog 1
Other 1 Cat 0
Digestive 1 Dog 0
Other 1 Dog 0

Species coverage: Dog (19) Cat (9)

View detailed reaction table
Reaction Body system Species Seriousness Frequency Reports
Other Cat Non-serious - 1
Digestive Dog Non-serious - 1
Other Dog Non-serious - 1
Other Cat Non-serious - 1
Neurologic Dog Non-serious - 1
Other Dog Serious - 1
Other Dog Non-serious - 1
Neurologic Dog Serious - 1
Other Dog Non-serious - 1
Other Cat Non-serious - 1
Other Dog Non-serious - 1
Other Dog Non-serious - 1
Other Cat Non-serious - 1
Effectiveness Dog Non-serious - 1
Effectiveness Cat Non-serious - 1
Skin & allergy Cat Non-serious - 1
Other Cat Non-serious - 1
Other Cat Non-serious - 1
Skin & allergy Dog Serious - 1
Other Dog Non-serious - 1
Other Dog Non-serious - 1
Other Dog Serious - 1
Skin & allergy Dog Non-serious - 1
Skin & allergy Dog Serious - 1
Behavior Cat Non-serious - 1
Other Dog Non-serious - 1
Other Dog Unknown - -
Other Dog Unknown - -
Source metadata:

Documents

Owner handouts and official technical documents open on-page first, with the original source still one click away.

Owner handouts

0
No owner handouts linked yet.

Official label / PI

2

SPL

2

FOI

3

COMFORTIS N141277.pdf

Official label / PI · Labeling

Open original

TRIFEXIS N141321C0060.pdf

Official label / PI · Official label

Open original

Comfortis®

SPL · SPL

Open original
FDA Structured Product Label

Comfortis®

Rendered from Roxee's cached FDA SPL package contents for on-page reading. Use Open original for the raw FDA ZIP/XML source.

Sponsor
Elanco US Inc.
NADA
141-277
Status
RX
Form
Tablet (Chewable)
Route
Oral
Species
Dog, No Use Class Stated Or Implied • Cat, No Use Class Stated Or Implied
Composition / specifications
Each chewable tablet contains 140, 270, 560, 810, or 1620 milligrams (mg) spinosad.

Dogs

Indication

To kill fleas and for the prevention and treatment of flea infestations (Ctenocephalides felis) for 1 month on dogs and puppies 14 weeks of age and older and 5.0 pounds or body weight or greater.

Dosage
Administer tablets once a month at a recommended minimum dosage of 13.5 mg per pound (30 mg per kilogram) of body weight.
Limitations
Federal law restricts this drug to use by or on the order of a licensed veterinarian.

Cats

Indication

To kill fleas and for the prevention and treatment of flea infestations (Ctenocephalides felis) for 1 month on cats and kittens 14 weeks of age and older and 4.1 pounds of body weight or greater.

Dosage
Administer tablets once a month at the minimum dosage of 22.5 mg per pound (50 mg per kilogram) of body weight.
Limitations
Federal law restricts this drug to use by or on the order of a licensed veterinarian.

Comfortis SPL

SPL · Structured Product Label

Open original
FDA Structured Product Label XML for Comfortis. Use the source link for the full official labeling record.

UCM326907.pdf

FOI · FOI

Open original

ucm062334.pdf

FOI · FOI

Open original

UCM252248.pdf

FOI · FOI summary

Open original
Source metadata:
Veterinary reference (advanced)

Canonical medication sections are above. This legacy block remains available for deeper cross-reference without cluttering the primary workflow.

At a Glance

Quick facts and links to official labeling and safety signals.

Data freshness
  • Storefront facts: Source Roxee | Refreshed May 5, 2026, 10:00 AM UTC
    The storefront fact projection used for browse cards and quick facts.
  • Animal Drugs @ FDA: Source FDA | Refreshed May 5, 2026, 10:00 AM UTC
    Applications/products are imported from FDA export data.
  • Animal Drugs @ FDA previews: Source FDA | Refreshed Feb 9, 2026, 3:05 AM UTC
    Label highlights/doc links are fetched from FDA preview endpoints.
  • Animal Drug Product Listing Directory (NDC): Source FDA | Refreshed May 5, 2026, 10:00 AM UTC
    Package/product NDCs from FDA’s electronic listing directory (XLS).
  • openFDA reaction terms: Source FDA openFDA | Refreshed May 5, 2026, 10:04 AM UTC
  • openFDA case summaries: Source FDA openFDA | Refreshed May 5, 2026, 10:04 AM UTC
Official (FDA)
Identity: Generic ingredient • FDA branded products available
Official FDA brands: Comfortis
Manufacturer mapping: Elanco US Inc.
Case-reported brands (openFDA): MSK
Catalog species: Both • FDA-labeled species: Cat, Dog
Rx/OTC: RX
Form/route: Tablet (Chewable) • Oral
Applications: NADA 141-277
NDC: Packages 58198-0071-1 58198-0071-2 58198-0072-1 58198-0072-2 58198-0073-1 58198-0073-2 • Products 58198
Documents: 3 (FOI: 2) • SPL: 1 • Label highlights • Official documents
Safety (openFDA)
Top reactions: Dog 7 • Cat 5 • View
Case summaries: 8 (showing 8) • View
openFDA reports are unverified and do not prove causation.
Explore
Related conditions: Fleas (Flea Infestation)
Linked using: Fda_Label (0.95)
Diagnosis Codes
ICD10_CM: B74.8 ICD10_CM: B88.1
Other filariases

Counseling and Monitoring Highlights

Global Pet owner/Vet mode is controlled in the header. This section avoids duplicate in-page persona tabs.

Owner-facing counseling points
  • Federal law restricts this drug to use by or on the order of a licensed veterinarian. Federal (USA) law restricts this drug to use by or on the order of a licensed veterinarian. Treatment with fewer than 3 monthly doses after the last exposure to mosquitos may not provide complete heartworm prevention. Use with caution in breeding females. The safe use of TRIFEXIS in breeding males has not been evaluated. Use with caution in dogs with pre-existing epilepsy. (Contraindication, High)
Top reaction signals
Skin scab (1) Seizure NOS (1) Generalised itching (1) Death (1) Biting - pruritus (1) Weight loss (1) Vomiting (1) UNPALATABLE (1)

Identifiers & Packages

Normalized identifiers (NDC/NADA/ANADA) and package metadata from regulator listings.

Identifiers
NADA: 141277 NADA: 141321 NDC Package: 58198-0042-1 NDC Package: 58198-0042-6 NDC Package: 58198-0043-1 NDC Package: 58198-0043-6 NDC Package: 58198-0044-1 NDC Package: 58198-0044-6 NDC Package: 58198-0045-1 NDC Package: 58198-0045-6 NDC Package: 58198-0046-1 NDC Package: 58198-0046-6 NDC Package: 58198-0071-1 NDC Package: 58198-0071-2 NDC Package: 58198-0072-1 NDC Package: 58198-0072-2 NDC Package: 58198-0073-1 NDC Package: 58198-0073-2 NDC Package: 58198-0074-1 NDC Package: 58198-0074-2 NDC Package: 58198-0075-1 NDC Package: 58198-0075-2 NDC Package: 73064-0305-1 NDC Product: 58198
Package NDC Product NDC Form / Route Status
58198-0042-1 58198 -
58198-0042-6 58198 -
58198-0043-1 58198 -
58198-0043-6 58198 -
58198-0044-1 58198 -
58198-0044-6 58198 -
58198-0045-1 58198 -
58198-0045-6 58198 -
58198-0046-1 58198 -
58198-0046-6 58198 -
58198-0071-1 58198 -
58198-0071-2 58198 -
58198-0072-1 58198 -
58198-0072-2 58198 -
58198-0073-1 58198 -
58198-0073-2 58198 -
58198-0074-1 58198 -
58198-0074-2 58198 -
58198-0075-1 58198 -
58198-0075-2 58198 -

Enriched Documents

Documents are tiered by source trust: Official, Clinical, Manufacturer, Marketing.

  • Comfortis SPL • Structured Product Label • Official
    FDA Structured Product Label from the electronic animal drug product listing directory.
  • COMFORTIS N141277.pdf • Official label • Official • May 17, 2021
    FDA official labeling for application 141277
  • ucm062334.pdf • FOI summary • Official • May 17, 2021
    FDA FOI summary for application 141277
  • UCM326907.pdf • FOI summary • Official • May 17, 2021
    FDA FOI summary for application 141277
  • TRIFEXIS N141321C0060.pdf • Official label • Official • May 17, 2021
    FDA official labeling for application 141321
  • UCM252248.pdf • FOI summary • Official • May 17, 2021
    FDA FOI summary for application 141321

Data Sources & Change Log

Every non-trivial field is expected to include provenance and update timestamps.

Official 41 Clinical 1 Manufacturer 0 Marketing 0
Current Field Facts
  • side_effects: Top reported reactions (openFDA): Vomiting, Lethargy (see also Central nervous system depression in 'Neurological'), Lack of efficacy (endoparasite) - heartwor… (Clinical, 2026-04-11)
  • contraindications: Federal law restricts this drug to use by or on the order of a licensed veterinarian. Federal (USA) law restricts this drug to use by or on the order of a lice… (Official, 2026-04-12)
  • contraindications: Federal law restricts this drug to use by or on the order of a licensed veterinarian. Federal (USA) law restricts this drug to use by or on the order of a lice… (Official, 2026-04-11)
  • contraindications: Federal law restricts this drug to use by or on the order of a licensed veterinarian. Federal (USA) law restricts this drug to use by or on the order of a lice… (Official, 2026-02-12)
  • indications: Kill fleas and are indicated for the prevention and treatment of flea infestations ( Ctenocephalides felis) on dogs for one month. 1) To add an indication for … (Official, 2026-05-05)
  • indications: Kill fleas and are indicated for the prevention and treatment of flea infestations ( Ctenocephalides felis) on dogs for one month. 1) To add an indication for … (Official, 2026-05-03)
  • indications: Kill fleas and are indicated for the prevention and treatment of flea infestations ( Ctenocephalides felis) on dogs for one month. 1) To add an indication for … (Official, 2026-05-02)
  • indications: Kill fleas and are indicated for the prevention and treatment of flea infestations ( Ctenocephalides felis) on dogs for one month. 1) To add an indication for … (Official, 2026-04-29)
  • indications: Kill fleas and are indicated for the prevention and treatment of flea infestations ( Ctenocephalides felis) on dogs for one month. 1) To add an indication for … (Official, 2026-04-28)
  • indications: Kill fleas and are indicated for the prevention and treatment of flea infestations ( Ctenocephalides felis) on dogs for one month. 1) To add an indication for … (Official, 2026-04-27)
  • indications: Kill fleas and are indicated for the prevention and treatment of flea infestations ( Ctenocephalides felis) on dogs for one month. 1) To add an indication for … (Official, 2026-04-26)
  • indications: Kill fleas and are indicated for the prevention and treatment of flea infestations ( Ctenocephalides felis) on dogs for one month. 1) To add an indication for … (Official, 2026-04-25)
  • indications: Kill fleas and are indicated for the prevention and treatment of flea infestations ( Ctenocephalides felis) on dogs for one month. 1) To add an indication for … (Official, 2026-04-22)
  • manufacturer_name: Elanco US Inc. (Official, 2026-05-05)
  • manufacturer_name: Elanco US Inc. (Official, 2026-05-03)
  • manufacturer_name: Elanco US Inc. (Official, 2026-05-02)
  • manufacturer_name: Elanco US Inc. (Official, 2026-04-29)
  • manufacturer_name: Elanco US Inc. (Official, 2026-04-28)
  • manufacturer_name: Elanco US Inc. (Official, 2026-04-27)
  • manufacturer_name: Elanco US Inc. (Official, 2026-04-26)
Recent Revisions
  • side_effects updated 2026-04-12 10:05 by etl_backfill • Backfilled from existing medication fields
  • contraindications updated 2026-04-12 10:05 by etl_backfill • Backfilled from existing medication fields
  • usage updated 2026-04-12 10:05 by etl_backfill • Backfilled from existing medication fields
  • side_effects updated 2026-04-11 10:05 by etl_backfill • Backfilled from existing medication fields
  • contraindications updated 2026-04-11 10:05 by etl_backfill • Backfilled from existing medication fields
  • usage updated 2026-04-11 10:05 by etl_backfill • Backfilled from existing medication fields
  • side_effects updated 2026-02-12 22:44 by etl_backfill • Backfilled from existing medication fields
  • contraindications updated 2026-02-12 22:44 by etl_backfill • Backfilled from existing medication fields
  • usage updated 2026-02-12 22:44 by etl_backfill • Backfilled from existing medication fields

FDA Products & Applications (Animal Drugs @ FDA)

Official sponsor/proprietary-name/application-status records linked by active ingredient.

Product Sponsor Application Status Published
Comfortis®
RX
Spinosad
Tablet (Chewable) • Oral
Label highlights
Official documents
Elanco US Inc. NADA 141-277 Approved May 17, 2021

Data source: FDA Animal Drugs @ FDA (public search export).

What It's For (FDA Label Highlights)

Extracted from FDA Animal Drugs @ FDA product labeling. Always confirm details with your veterinarian.

Species: Dog, No Use Class Stated Or Implied • Cat, No Use Class Stated Or Implied
Composition / specifications
Each chewable tablet contains 140, 270, 560, 810, or 1620 milligrams (mg) spinosad.
Dogs
Indication

To kill fleas and for the prevention and treatment of flea infestations (Ctenocephalides felis) for 1 month on dogs and puppies 14 weeks of age and older and 5.0 pounds or body weight or greater.

Dosage
Administer tablets once a month at a recommended minimum dosage of 13.5 mg per pound (30 mg per kilogram) of body weight.
Limitations
Federal law restricts this drug to use by or on the order of a licensed veterinarian.
Cats
Indication

To kill fleas and for the prevention and treatment of flea infestations (Ctenocephalides felis) for 1 month on cats and kittens 14 weeks of age and older and 4.1 pounds of body weight or greater.

Dosage
Administer tablets once a month at the minimum dosage of 22.5 mg per pound (50 mg per kilogram) of body weight.
Limitations
Federal law restricts this drug to use by or on the order of a licensed veterinarian.

FDA page: Open in Animal Drugs @ FDA

Usage

To kill fleas and for the prevention and treatment of flea infestations ( Ctenocephalides felis ) for 1 month on dogs and puppies 14 weeks of age and older and 5.0 pounds or body weight or greater. To kill fleas and for the prevention and treatment of flea infestations ( Ctenocephalides felis ) for 1 month on cats and kittens 14 weeks of age and older and 4.1 pounds of body weight or greater. Trifexis™ Chewable Tablets kill fleas and are indicated for the prevention and treatment of flea infestations ( Ctenocephalides felis ), and the treatment and control of adult hookworm ( Ancylostoma caninum ), adult roundworm ( Toxocara canis and Toxascaris leonina ) and adult whipworm ( Trichuris vulpis ) infections in dogs and puppies 8 weeks of age or older and 5 pounds of body weight or greater.

Source: FDA Animal Drugs @ FDA • Reference

Contraindications

Federal law restricts this drug to use by or on the order of a licensed veterinarian. Federal (USA) law restricts this drug to use by or on the order of a licensed veterinarian. Treatment with fewer than 3 monthly doses after the last exposure to mosquitos may not provide complete heartworm prevention. Use with caution in breeding females. The safe use of TRIFEXIS in breeding males has not been evaluated. Use with caution in dogs with pre-existing epilepsy.

Top Reported Reactions (openFDA)

De-duplicated reaction terms grouped by body system from FDA openFDA reports (not verified; does not prove causation).

Digestive
Vomiting (1) • Dog

Showing top 5 for Digestive.

Skin & allergy
Itching (1) • Cat Generalised itching (1) • Dog Chewing - pruritus (1) • Dog Biting - pruritus (1) • Dog

Showing top 5 for Skin & allergy.

Neurologic
Tiredness (1) • Dog Seizure NOS (1) • Dog

Showing top 5 for Neurologic.

Behavior
Behavioral disorder (1) • Cat

Showing top 5 for Behavior.

Effectiveness
Lack of efficacy (endoparasite) - heartworm (1) • Dog Lack of efficacy (ectoparasite) - flea (1) • Cat

Showing top 5 for Effectiveness.

Other
Weight loss (1) • Cat UNPALATABLE (1) • Dog Tongue protrusion (1) • Cat Skin scab (1) • Dog Shaking (1) • Dog
Show more (13)
Scratching (1) • Dog Panting (1) • Cat Overdose (1) • Dog Malaise (1) • Dog Licking (1) • Cat Incorrect dose administered NOS (1) • Cat Hyperactivity (1) • Cat Falling (1) • Dog Difficulty standing (1) • Dog Death (1) • Dog Accidental exposure (1) • Dog Arthritis • Dog Administration error NOS • Dog

Showing top 5 for Other.

Data source: FDA openFDA Animal & Veterinary adverse event reports.

Adverse Event Case Summaries (openFDA)

These are individual FDA adverse event reports. They are unverified and do not prove the medication caused the reaction.

Dog, Poodle - Miniature, Male, 17 year, 8.618 kilogram • Drug: MSK, Tablet, Oral, Dose: 1 tablet per animal • Reactions: Lack of efficacy (ectoparasite) - flea • Outcome: Ongoing

  • Report ID: USA-USFDACVM-2025-US-074769
  • Serious AE: No
  • Treated For AE: Yes
  • Sex: Male
  • Age: 17.00 Year
  • Weight: 8.618 Kilogram
  • Case-reported brand: MSK
  • Case-reported manufacturer: MSK
  • Route: Oral
  • Form: Tablet
  • Dose: 1 tablet per animal
Reactions Reported:
Lack of efficacy (ectoparasite) - flea
Outcomes: Ongoing

Dog, ['Poodle - Miniature', 'Dog (unknown)'], Male, 17 year, 8.618 kilogram • Drug: MSK, Tablet, chewable, Oral, Dose: 1 tablet per animal • Reactions: Scratching, Lack of efficacy (ectoparasite) - flea • Outcome: Ongoing

  • Report ID: USA-USFDACVM-2025-US-071144
  • Serious AE: No
  • Treated For AE: Yes
  • Sex: Male
  • Age: 17.00 Year
  • Weight: 8.618 Kilogram
  • Case-reported brand: MSK
  • Case-reported manufacturer: MSK
  • Route: Oral
  • Form: Tablet, chewable
  • Dose: 1 tablet per animal
Reactions Reported:
Scratching Lack of efficacy (ectoparasite) - flea
Outcomes: Ongoing

Cat, Domestic Shorthair, Female, 1.49 year, 3.62 kilogram • Drug: MSK, Tablet, chewable, Oral, Dose: 1 tablet per animal • Reactions: Vomiting, Incorrect dose administered NOS • Outcome: Recovered/Normal

  • Report ID: USA-USFDACVM-2025-US-066982
  • Serious AE: No
  • Treated For AE: Yes
  • Sex: Female
  • Age: 1.49 Year
  • Weight: 3.620 Kilogram
  • Case-reported brand: MSK
  • Case-reported manufacturer: MSK
  • Route: Oral
  • Form: Tablet, chewable
  • Dose: 1 tablet per animal
Reactions Reported:
Vomiting Incorrect dose administered NOS
Outcomes: Recovered/Normal

Dog, ['Shepherd Dog - Australian', 'Dog (unknown)'], Unknown, 8 year, 54.4 kilogram • Drug: MSK, Tablet, chewable, Oral, Dose: 1 tablet per animal • Reactions: Biting - pruritus, Skin scab, Chewing - pruritus, Generalised itching, Lack of efficacy (ectoparasite) - flea • Outcome: Ongoing

  • Report ID: USA-USFDACVM-2025-US-067101
  • Serious AE: No
  • Treated For AE: Yes
  • Sex: Unknown
  • Age: 8.00 Year
  • Weight: 54.400 Kilogram
  • Case-reported brand: MSK
  • Case-reported manufacturer: MSK
  • Route: Oral
  • Form: Tablet, chewable
  • Dose: 1 tablet per animal
Reactions Reported:
Biting - pruritus Skin scab Chewing - pruritus Generalised itching Lack of efficacy (ectoparasite) - flea
Outcomes: Ongoing

Dog, ['Pit Bull', 'Boxer (German Boxer)'], Female, 9 year, 45.5 kilogram • Drug: MSK, Tablet, chewable, Oral, Dose: 1 tablet per animal • Reactions: Biting - pruritus, Lack of efficacy (ectoparasite) - flea, Generalised itching, Skin scab, Seizure NOS • Outcome: Ongoing

  • Report ID: USA-USFDACVM-2025-US-066601
  • Serious AE: Yes
  • Treated For AE: Yes
  • Sex: Female
  • Age: 9.00 Year
  • Weight: 45.500 Kilogram
  • Case-reported brand: MSK
  • Case-reported manufacturer: MSK
  • Route: Oral
  • Form: Tablet, chewable
  • Dose: 1 tablet per animal
Reactions Reported:
Biting - pruritus Lack of efficacy (ectoparasite) - flea Generalised itching Skin scab Seizure NOS
Outcomes: Ongoing

Cat, Domestic Shorthair, Male, 5 year, 6.08 kilogram • Drug: MSK, Tablet, chewable, Oral, Dose: 1 tablet per animal • Reactions: Lack of efficacy (ectoparasite) - flea • Outcome: Outcome Unknown

  • Report ID: USA-USFDACVM-2025-US-065550
  • Serious AE: No
  • Treated For AE: No
  • Sex: Male
  • Age: 5.00 Year
  • Weight: 6.080 Kilogram
  • Case-reported brand: MSK
  • Case-reported manufacturer: MSK
  • Route: Oral
  • Form: Tablet, chewable
  • Dose: 1 tablet per animal
Reactions Reported:
Lack of efficacy (ectoparasite) - flea
Outcomes: Outcome Unknown

Cat, Domestic Mediumhair, Female, 6 year, 4.082 kilogram • Drug: MSK, Tablet, chewable, Oral, Dose: 1 tablet per animal • Reactions: Vomiting • Outcome: Recovered/Normal

  • Report ID: USA-USFDACVM-2025-US-061961
  • Serious AE: No
  • Treated For AE: No
  • Sex: Female
  • Age: 6.00 Year
  • Weight: 4.082 Kilogram
  • Case-reported brand: MSK
  • Case-reported manufacturer: MSK
  • Route: Oral
  • Form: Tablet, chewable
  • Dose: 1 tablet per animal
Reactions Reported:
Vomiting
Outcomes: Recovered/Normal

Cat, Domestic Shorthair, Male, 17 year, 4.53 kilogram • Drug: MSK, Tablet, chewable, Oral, Dose: 1 tablet per animal • Reactions: Behavioral disorder (unspecified), UNPALATABLE • Outcome: Outcome Unknown

  • Report ID: USA-USFDACVM-2025-US-060557
  • Serious AE: No
  • Treated For AE: No
  • Sex: Male
  • Age: 17.00 Year
  • Weight: 4.530 Kilogram
  • Case-reported brand: MSK
  • Case-reported manufacturer: MSK
  • Route: Oral
  • Form: Tablet, chewable
  • Dose: 1 tablet per animal
Reactions Reported:
Behavioral disorder (unspecified) UNPALATABLE
Outcomes: Outcome Unknown

Data source: FDA openFDA Animal & Veterinary adverse event reports.

Overdose Information

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Storage & Handling

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