Meds A-Z
Spinosad
Detailed information about Spinosad
Pet Owner Quick Guide
Start here: what this medicine is for, what it does, and when it's usually needed.
Usually 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.
What it does:
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...
When it's needed:
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...
Call your vet sooner if you notice:
- 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.
Commonly reported reactions:
- (2 reports)
- (2 reports)
- (1 reports)
What to 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?
Spinosad
Drug type: Generic ingredient • Branded profile • FDA branded products available
Species: Both
Manufacturer: MSK
Quick Facts
Official label facts first, then secondary summaries. Marketing content is separated below.
- https://animaldrugsatfda.fda.gov/adafda/views/#/home/previewsearch/141277 · official_label · FDA application profile
- https://animaldrugsatfda.fda.gov/adafda/views/#/home/previewsearch/141321 · official_label · FDA application profile
- https://animaldrugsatfda.fda.gov · fda_animal_drugs · Medication usage source
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.
- https://animaldrugsatfda.fda.gov · fda_animal_drugs · Contraindication source
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.
Most Reported Reactions
| Reaction | Cases | Species | Serious cases |
|---|---|---|---|
| 2 | Cat, Dog | 0 | |
| 2 | Cat, Dog | 0 | |
| 1 | Dog | 1 | |
| 1 | Cat | 0 | |
| 1 | Cat | 0 | |
| 1 | Cat | 0 | |
| 1 | Dog | 0 | |
| 1 | Cat | 0 |
Species coverage: Dog (19) Cat (13)
View detailed reaction table
| Reaction | Species | Seriousness | Frequency | Reports |
|---|---|---|---|---|
| Cat | Non-serious | - | 1 | |
| Dog | Serious | - | 1 | |
| Cat | Non-serious | - | 1 | |
| Cat | Non-serious | - | 1 | |
| Cat | Non-serious | - | 1 | |
| Dog | Non-serious | - | 1 | |
| Cat | Non-serious | - | 1 | |
| Cat | Non-serious | - | 1 | |
| Cat | Non-serious | - | 1 | |
| Cat | Non-serious | - | 1 | |
| Dog | Non-serious | - | 1 | |
| Cat | Non-serious | - | 1 | |
| Dog | Non-serious | - | 1 | |
| Cat | Unknown | - | - | |
| Dog | Unknown | - | - | |
| Dog | Unknown | - | - | |
| Dog | Unknown | - | - | |
| Dog | Unknown | - | - | |
| Dog | Unknown | - | - | |
| Dog | Unknown | - | - | |
| Dog | Unknown | - | - | |
| Dog | Unknown | - | - | |
| Dog | Unknown | - | - | |
| Dog | Unknown | - | - | |
| Dog | Unknown | - | - | |
| Dog | Unknown | - | - | |
| Cat | Unknown | - | - | |
| Cat | Unknown | - | - | |
| Cat | Unknown | - | - | |
| Dog | Unknown | - | - | |
| Dog | Unknown | - | - | |
| Dog | Unknown | - | - |
- https://api.fda.gov/animalandveterinary/event.json · adverse_reaction · openFDA case USA-USFDACVM-2025-US-038822
Storage & Handling
No storage/handling guidance is linked yet.
Documents
Official label facts are separated from secondary summaries.
Official documents: 7 • Secondary summaries: 0
- UCM326907.pdf · FOI
- ucm062334.pdf · FOI
- COMFORTIS N141277.pdf · Labeling
- Comfortis® · SPL
- UCM252248.pdf · FOI
- TRIFEXIS N141321C0060.pdf · Labeling
- Trifexis™ · SPL
No source yet.
- https://animaldrugsatfda.fda.gov/adafda/app/search/public/document/downloadFoi/838 · document · FOI
- https://animaldrugsatfda.fda.gov/adafda/app/search/public/document/downloadFoi/837 · document · FOI
- https://animaldrugsatfda.fda.gov/adafda/app/search/public/document/downloadLabeling/883 · document · Labeling
- https://animaldrugsatfda.fda.gov/adafda/app/search/public/spl/file/214/Comfortis%C2%AE · document · SPL
- https://animaldrugsatfda.fda.gov/adafda/app/search/public/document/downloadFoi/878 · document · FOI
- https://animaldrugsatfda.fda.gov/adafda/app/search/public/document/downloadLabeling/913 · document · Labeling
- https://animaldrugsatfda.fda.gov/adafda/app/search/public/spl/file/2207/Trifexis%E2%84%A2 · document · SPL
Promotional Materials (Marketing)
This content is marketing material and not clinical guidance.
No marketing assets are linked yet.
No source yet.
Technical appendix (vet reference)
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.
- Medication catalog: Source PetWisePlus | Refreshed Feb 12, 2026, 10:44 PM UTC
-
Animal Drugs @ FDA:
Source FDA
| Refreshed Feb 16, 2026, 11:00 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 Feb 16, 2026, 11:00 AM UTC
Package/product NDCs from FDA’s electronic listing directory (XLS).
- openFDA reaction terms: Source FDA openFDA | Refreshed Feb 16, 2026, 11:02 AM UTC
- openFDA case summaries: Source FDA openFDA | Refreshed Feb 9, 2026, 3:19 AM UTC
Counseling and Monitoring Highlights
Global Pet owner/Vet mode is controlled in the header. This section avoids duplicate in-page persona tabs.
- 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)
Identifiers & Packages
Normalized identifiers (NDC/NADA/ANADA) and package metadata from regulator listings.
| 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.
-
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
-
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
Data Sources & Revision History
Every non-trivial field is expected to include provenance and update timestamps.
- 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)
- side_effects: Top reported reactions (openFDA): Vomiting, Lethargy (see also Central nervous system depression in 'Neurological'), Lack of efficacy (endoparasite) - heartwor… (Official, 2026-02-12)
- 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… (Official, 2026-02-12)
- 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
|
Elanco US Inc. | NADA 141-277 | Approved | May 17, 2021 |
|
Trifexis™
RX
Milbemycin Oxime Spinosad
Chewable Tablets
• Oral
|
Elanco US Inc. | NADA 141-321 | 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.
Composition / specifications
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.
FDA page: Open in Animal Drugs @ FDA
Composition / specifications
140 mg spinosad and 2.3 mg milbemycin oxime
270 mg spinosad and 4.5 mg milbemycin oxime
560 mg spinosad and 9.3 mg milbemycin oxime
810 mg spinosad and 13.5 mg milbemycin oxime
1620 mg spinosad and 27 mg milbemycin oxime
FDA page: Open in Animal Drugs @ FDA
Official Documents (FDA)
Direct links to FDA-hosted PDFs and SPL packages (when available).
-
FOI UCM326907.pdf
Summary
1) To add an indication for use in cats: Kills fleas and is indicated for the prevention and treatment of flea infestations (Ctenocephalides felis) for one month in cats and kittens 14 weeks of age and older, and two pounds of body weight or greater, and 2) add the 90 mg dose band for use of Comfortis® in dogs. -
FOI ucm062334.pdf
Summary
Kill fleas and are indicated for the prevention and treatment of flea infestations ( Ctenocephalides felis) on dogs for one month. -
Labeling COMFORTIS N141277.pdf
- Comfortis® (ZIP)
FDA page: Open in Animal Drugs @ FDA
-
FOI UCM252248.pdf
Summary
Indicated for the prevention of heartworm disease ( Dirofilaria immitis). 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. -
Labeling TRIFEXIS N141321C0060.pdf
- Trifexis™ (ZIP)
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.
Side Effects
No approved side-effect narrative is linked yet.
openFDA reaction signals are available for Dog 56 and Cat 20 (view top reported reactions).
Top Reported Reactions (openFDA)
Aggregated reaction terms from FDA openFDA reports (not verified; does not prove causation).
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, Crossbred Canine/dog, Female, 11 year, 26.2 kilogram • Drug: MSK, Tablet, chewable, Oral, Dose: 810 Milligram per animal • Reactions: Lack of efficacy (endoparasite) - heartworm • Outcome: Outcome Unknown
- Report ID: USA-USFDACVM-2025-US-055803
- Serious AE: No
- Treated For AE: No
- Sex: Female
- Age: 11.00 Year
- Weight: 26.200 Kilogram
- Case-reported brand: MSK
- Case-reported manufacturer: MSK
- Route: Oral
- Form: Tablet, chewable
- Dose: 810 Milligram per animal
Dog, Terrier - Yorkshire, Female, 9.25 year, 3.76 kilogram • Drug: MSK, Tablet, chewable, Oral, Dose: 1 dose per animal, Frequency: 1 per month • Reactions: Lack of efficacy (endoparasite) - heartworm • Outcome: Outcome Unknown
- Report ID: USA-USFDACVM-2025-US-056111
- Serious AE: No
- Treated For AE: No
- Sex: Female
- Age: 9.25 Year
- Weight: 3.760 Kilogram
- Case-reported brand: MSK
- Case-reported manufacturer: MSK
- Route: Oral
- Form: Tablet, chewable
- Dose: 1 dose per animal
- Frequency: 1 per month
Dog, ['Shepherd Dog - German', 'Dog (unknown)'], Male, 7.92 year • Drug: MSK, Tablet, chewable, Oral, Dose: 1 tablet per animal, Frequency: 1 per month • Reactions: Lack of efficacy (endoparasite) - heartworm, Weight loss • Outcome: Outcome Unknown
- Report ID: USA-USFDACVM-2025-US-055771
- Serious AE: No
- Treated For AE: Yes
- Sex: Male
- Age: 7.92 Year
- Case-reported brand: MSK
- Case-reported manufacturer: MSK
- Route: Oral
- Form: Tablet, chewable
- Dose: 1 tablet per animal
- Frequency: 1 per month
Dog, Retriever - Labrador, Female, 4 year, 32.2 kilogram • Drug: MSK, Tablet, chewable, Oral, Dose: 1 tablet per animal, Frequency: 1 per month • Reactions: Vomiting • Outcome: Recovered/Normal
- Report ID: USA-USFDACVM-2025-US-054533
- Serious AE: No
- Treated For AE: No
- Sex: Female
- Age: 4.00 Year
- Weight: 32.200 Kilogram
- Case-reported brand: MSK
- Case-reported manufacturer: MSK
- Route: Oral
- Form: Tablet, chewable
- Dose: 1 tablet per animal
- Frequency: 1 per month
Dog, Dog (unknown), Unknown • Drug: MSK, Tablet, chewable, Oral, Dose: 1620 Milligram per animal, Frequency: 1 per month • Reactions: Death • Outcome: Died
- Report ID: USA-USFDACVM-2025-US-055624
- Serious AE: Yes
- Treated For AE: No
- Sex: Unknown
- Case-reported brand: MSK
- Case-reported manufacturer: MSK
- Route: Oral
- Form: Tablet, chewable
- Dose: 1620 Milligram per animal
- Frequency: 1 per month
Cat, Domestic Shorthair, Female, 15 year, 3.175 kilogram • Drug: MSK, Tablet, chewable, Oral, Dose: 1 tablet per animal • Reactions: Tongue protrusion, Hyperactivity, Licking, Panting • Outcome: Outcome Unknown
- Report ID: USA-USFDACVM-2025-US-047977
- Serious AE: No
- Treated For AE: No
- Sex: Female
- Age: 15.00 Year
- Weight: 3.175 Kilogram
- Case-reported brand: MSK
- Case-reported manufacturer: MSK
- Route: Oral
- Form: Tablet, chewable
- Dose: 1 tablet per animal
Cat, Domestic Shorthair, Male, 3.49 year, 6.12 kilogram • Drug: MSK, Tablet, chewable, Oral, Dose: 1 tablet per animal • Reactions: Vomiting • Outcome: Recovered/Normal
- Report ID: USA-USFDACVM-2025-US-048242
- Serious AE: No
- Treated For AE: No
- Sex: Male
- Age: 3.49 Year
- Weight: 6.120 Kilogram
- Case-reported brand: MSK
- Case-reported manufacturer: MSK
- Route: Oral
- Form: Tablet, chewable
- Dose: 1 tablet per animal
Cat, Domestic Shorthair, Male, 10 year, 4.99 kilogram • Drug: MSK, Tablet, chewable, Oral, Dose: 1 tablet per animal • Reactions: Weight loss • Outcome: Ongoing
- Report ID: USA-USFDACVM-2025-US-045171
- Serious AE: No
- Treated For AE: No
- Sex: Male
- Age: 10.00 Year
- Weight: 4.990 Kilogram
- Case-reported brand: MSK
- Case-reported manufacturer: MSK
- Route: Oral
- Form: Tablet, chewable
- Dose: 1 tablet per animal
Data source: FDA openFDA Animal & Veterinary adverse event reports.
Overdose Information
No approved overdose-management text is linked yet. If overdose is suspected, contact a veterinarian or emergency clinic immediately.
Storage & Handling
No approved storage guidance is linked yet for this ingredient. Use manufacturer packaging and veterinary guidance for handling/storage.
Share Your Thoughts
Let others know your experience or advice regarding this medication.
This medication has not been reviewed by a veterinarian yet.