Pet Drug Reports

Ingredients

Active ingredient · pooled across combinations

Spinosad: adverse event reports, pooled

3 ingredient sets in reports · 2 FDA-approved applications in the Green Book

212,330reports naming the ingredient, 2007–202615.6% of all reports · about 11,225 a year
832reports, 12 months to March 2026942 in the 12 months before
11.7%classed serious, as reportedall reports: 38.6%
87.4%of reports concern dogscat 5.6%

212,330 adverse event reports received by FDA list a drug containing spinosad, alone or in combination, from May 2007 to March 2026. This page pools every ingredient set that includes it; 3 such sets appear in reports.

The Green Book lists 2 FDA-approved applications containing it. openFDA masks brand and manufacturer names in adverse event records, so the reports counted here cannot be attributed to a particular brand.

832 reports arrived in the 12 months to March 2026, down 12% from 942 in the 12 months before. FDA posts reports quarterly with a delay of three to six months, so the newest months are incomplete and usually grow in later releases. That is about 11,225 reports a year over its reporting history and 15.6% of all reports.

Pooled across every set, the terms listed most often are emesis (28.3%), vomiting (24.3%) and lethargy (11.2%). Many drugs combine several ingredients, and many reports list several drugs, so a term on this page may relate to any of them or to none.

Of reports that state seriousness, 11.7% were classed as serious (38.6% across the whole database); 2.5% record a death or euthanasia (6.4% overall). Ingredients used in older or sicker animals, or in anaesthesia and cancer care, carry higher shares for that reason alone.

Ingredient sets that include spinosad

Active ingredients recorded for the drugReportsShare of this page's reportsLatest 12 months
Milbemycin Oxime + Spinosad140,67366.3%754
Spinosad72,82534.3%82
Lufenuron + Milbemycin Oxime + Spinosad10%0

Ordered by report count. FDA states that these data "cannot be used to estimate the risk associated with the product or compare one drug or device product with another"; counts follow sales volume and years on the market. A report can list more than one set, so shares can add to more than 100%.

Signs listed in reports, pooled

share of spinosad reports listing the termall reports in the database

  1. Emesis[vomiting]28.3%60,054
  2. Vomiting24.3%51,506
  3. Lethargy[unusually tired or inactive]11.2%23,717
  4. Lack of efficacy (ectoparasite) - flea[the product did not have the expected effect: fleas]9.9%21,071
  5. Unpalatable[legacy FDA term: the animal would not take it]8.1%17,115
  6. Lack of efficacy - NOS[the product did not have the expected effect]6.6%13,957
  7. Diarrhoea[diarrhea]4.2%8,985
  8. Ineffective, heartworm larvae[legacy FDA term: the product did not have the expected effect (heartworm larvae)]2.7%5,672
  9. Seizure NOS[seizure, type not specified]2.6%5,429
  10. Lack of efficacy (endoparasite) - heartworm[the product did not have the expected effect: heartworm]2.4%5,093
  11. Behavioural disorder NOS[behaviour change, type not specified]2.4%5,071
  12. Anorexia[not eating]2.2%4,693
  13. Depression[dull, quiet or withdrawn]2.1%4,353
  14. Ataxia[unsteady, uncoordinated movement]1.9%4,042
  15. Pruritus[itching]1.9%4,021
  16. Shaking1.7%3,531
  17. Product problem[a product quality report, not a sign in an animal]1.6%3,489
  18. Emesis (multiple)[vomiting more than once]1.6%3,419
  19. Itching1.6%3,334
  20. Accidental exposure[exposure that was not intended]1.5%3,272
  21. Not eating1.5%3,219
  22. Other abnormal test result NOS[abnormal laboratory result, type not specified]1.5%3,185
  23. Death1.4%3,009
  24. Lack of efficacy (endoparasite) - hookworm[the product did not have the expected effect: hookworms]1.4%2,988
  25. Weight gain1.4%2,935
  26. Overdose[more than the labelled amount was given]1.4%2,889
  27. Trembling1.4%2,879
  28. Weight loss1.2%2,651
  29. Lack of efficacy (flea)[the product did not have the expected effect: fleas]1.2%2,518

Pooled across every ingredient set and every report that names the ingredient. One report can list several terms and several drugs; a term here may relate to any of them or to none.

Monthly reports by species, five years

Dog7,053 · peak 293
Apr 2021: 293May 2021: 232Jun 2021: 285Jul 2021: 276Aug 2021: 210Sep 2021: 226Oct 2021: 215Nov 2021: 173Dec 2021: 146Jan 2022: 148Feb 2022: 135Mar 2022: 200Apr 2022: 160May 2022: 214Jun 2022: 134Jul 2022: 186Aug 2022: 181Sep 2022: 145Oct 2022: 140Nov 2022: 109Dec 2022: 108Jan 2023: 119Feb 2023: 78Mar 2023: 128Apr 2023: 120May 2023: 136Jun 2023: 128Jul 2023: 101Aug 2023: 117Sep 2023: 92Oct 2023: 83Nov 2023: 108Dec 2023: 81Jan 2024: 75Feb 2024: 101Mar 2024: 84Apr 2024: 92May 2024: 83Jun 2024: 81Jul 2024: 70Aug 2024: 76Sep 2024: 85Oct 2024: 86Nov 2024: 59Dec 2024: 46Jan 2025: 43Feb 2025: 67Mar 2025: 47Apr 2025: 61May 2025: 81Jun 2025: 90Jul 2025: 84Aug 2025: 64Sep 2025: 64Oct 2025: 73Nov 2025: 38Dec 2025: 45Jan 2026: 63Feb 2026: 50Mar 2026: 382022202320242025
Cat368 · peak 28
Apr 2021: 23May 2021: 18Jun 2021: 26Jul 2021: 19Aug 2021: 28Sep 2021: 15Oct 2021: 18Nov 2021: 6Dec 2021: 4Jan 2022: 9Feb 2022: 7Mar 2022: 8Apr 2022: 2May 2022: 8Jun 2022: 8Jul 2022: 7Aug 2022: 10Sep 2022: 8Oct 2022: 10Nov 2022: 8Dec 2022: 2Jan 2023: 2Feb 2023: 8Mar 2023: 1Apr 2023: 8May 2023: 4Jun 2023: 6Jul 2023: 6Aug 2023: 4Sep 2023: 3Oct 2023: 2Nov 2023: 7Dec 2023: 5Jan 2024: 4Feb 2024: 1Mar 2024: 2Apr 2024: 1May 2024: 7Jul 2024: 3Aug 2024: 4Sep 2024: 2Oct 2024: 8Nov 2024: 1Dec 2024: 4Jan 2025: 2Feb 2025: 7Mar 2025: 2May 2025: 6Jun 2025: 2Jul 2025: 1Aug 2025: 3Oct 2025: 3Nov 2025: 1Jan 2026: 3Feb 2026: 12022202320242025
Horse0 · peak 1
2022202320242025
Other563 · peak 36
Apr 2021: 30May 2021: 24Jun 2021: 36Jul 2021: 30Aug 2021: 26Sep 2021: 17Oct 2021: 11Nov 2021: 11Dec 2021: 10Jan 2022: 4Feb 2022: 18Mar 2022: 14Apr 2022: 20May 2022: 17Jun 2022: 13Jul 2022: 10Aug 2022: 7Sep 2022: 7Oct 2022: 8Nov 2022: 6Dec 2022: 12Jan 2023: 6Feb 2023: 3Mar 2023: 8Apr 2023: 6May 2023: 8Jun 2023: 8Jul 2023: 11Aug 2023: 3Sep 2023: 8Oct 2023: 7Nov 2023: 5Dec 2023: 13Jan 2024: 5Feb 2024: 6Mar 2024: 8Apr 2024: 3May 2024: 3Jun 2024: 3Jul 2024: 9Aug 2024: 6Sep 2024: 5Oct 2024: 2Nov 2024: 4Dec 2024: 5Jan 2025: 10Feb 2025: 5Mar 2025: 11Apr 2025: 8May 2025: 7Jun 2025: 10Jul 2025: 5Aug 2025: 4Sep 2025: 5Oct 2025: 4Nov 2025: 1Dec 2025: 5Jan 2026: 4Feb 2026: 5Mar 2026: 32022202320242025

By month of receipt; each panel has its own scale. The newest months are incomplete because FDA posts reports with a delay of three to six months.

017,94335,8852007: 5620072008: 3,3452009: 3,60220092010: 9,0032011: 17,25420112012: 32,5822013: 35,88520132014: 27,3092015: 22,50620152016: 16,4212017: 12,75920172018: 9,5542019: 7,43520192020: 5,6652021: 3,37820212022: 2,0832023: 1,43320232024: 1,0342025: 85920252026: 167

Outcomes, report types and ages

Outcome recorded in the report

Recovered/Normal49.3%104,704
Recovered with Sequela4.6%9,790
Ongoing4.4%9,263
Died1.7%3,657
Euthanized0.8%1,647
Outcome Unknown22%46,609

What kind of report it was

Safety issue72.9%154,709
Lack of expected effectiveness11.2%23,777
Both safety and lack of expected effectiveness4%8,578
Manufacturing or product defect11.9%25,253
Other0%13

Species

Dog87.4%185,564
Cat5.6%11,867
Human exposure0.2%454
Other0%16
Other Canids0%14
Wolf0%2

Age of the animal

Under 1 year13.2%28,071
1 to 3 years32%67,970
4 to 7 years23.2%49,165
8 to 11 years12.4%26,301
12 years and over5.5%11,773
Age not given13.7%29,050

Coloured bar: reports naming spinosad. Grey bar: all 1,357,245 reports. Outcomes are as stated by the reporter; FDA has not necessarily determined whether any product played a part.

In context

MeasureSpinosadAll reports
Reports212,3301,357,245
Latest 12 months against the 12 before-12%-5%
Classed serious, of reports stating it11.7%38.6%
Death or euthanasia recorded, per 1,000 reports2563.8
Filed as lack of expected effectiveness (wholly or partly)15.2%23%

Shares of reports, not of animals treated: how many animals receive the ingredient is not public. Ingredients used in anaesthesia, cancer care or in old animals carry more serious outcomes in their reports for that reason alone.

FDA-approved products containing spinosad (Green Book)

Reference information, not report statistics. openFDA masks brand and manufacturer names in adverse event records, so the reports counted here cannot be attributed to a particular brand. The list below is the FDA Green Book as of 30 Sep 2026; nothing on this page says which of these products, if any, a report concerned.

Trade nameActive ingredientsSponsorApproved forApplication
ComfortisSpinosadElanco US Inc.Dogs, CatsNADA 141-277
TrifexisMilbemycin Oxime, SpinosadElanco US Inc.DogsNADA 141-321

Species are the major species the Green Book search lists for the application ("—" where it lists another species or none). Approval dates are not part of the Green Book listing files and are not shown. Pioneer applications (NADA) come first, then generics (ANADA).

Questions about spinosad reports

How many FDA adverse event reports mention spinosad?

212,330 reports through March 2026, 832 of them in the latest 12 months, counting spinosad alone and in combinations.

Which brands do these reports concern?

That cannot be known from the public data. openFDA masks brand and manufacturer names in adverse event records, so the reports counted here cannot be attributed to a particular brand. The Green Book reference list on this page names approved products containing spinosad without any counts.

In which combinations is spinosad reported?

Milbemycin Oxime + Spinosad (66.3% of these reports), Spinosad (34.3% of these reports) and Lufenuron + Milbemycin Oxime + Spinosad (0% of these reports).

What reactions are reported for spinosad?

emesis (28.3%), vomiting (24.3%), lethargy (11.2%), lack of efficacy (ectoparasite) - flea (9.9%) and unpalatable (8.1%). Shares are of reports naming the ingredient; one report can list several terms.

Which animals are these reports about?

dog (87.4%), cat (5.6%) and human exposure (0.2%).

Does a high count mean spinosad is a problem ingredient?

A count cannot show that. FDA states that "there is no certainty that the reported drug or device caused the adverse event" and that the event "may have been related to an underlying disease, other drugs used at the same time or other non-drug related sources." Widely used ingredients collect more reports because more animals receive them.

How do I report a problem?

Call the drug company using the number on the label, or send Form FDA 1932a to FDA. See the guide on how to report.

Where this comes from. Counts are built from the openFDA Animal & Veterinary adverse event bulk files released 28 Sep 2026, which hold reports FDA's Center for Veterinary Medicine received through 31 Mar 2026. openFDA masks brand and manufacturer names in these files, so drugs are counted by the active ingredients each record discloses and no figure is attributed to a brand, application or company. Ingredient names, and the separate reference lists of approved products, follow the FDA Green Book as of 30 Sep 2026. Ingredient names follow the Green Book; salts and forms are kept as FDA lists them. Drug entries are matched by the active ingredients their unmasked ingredient field discloses. No report text, lot numbers or reporter details are published. See the methodology and sources; FDA's record is authoritative, and corrections are handled within five working days.