Pyrethrins: adverse event reports in all combinations
Active ingredient, alone and in combinations
The openFDA records give the value "MSK" for the brand name and for the manufacturer name of each drug. FDA says that MSK means "masked". So the site cannot count a report for a brand.
Read this first. FDA says this about the data:
An API dataset query result cannot be used to estimate the risk associated with the product or compare one drug or device product with another. When looking at the results, be aware that there is no certainty that the reported drug or device caused the adverse event. This dataset should not be the sole source of information for clinical decision-making or other assumptions about the safety or effectiveness of a product. The adverse event may have been related to an underlying disease, other drugs used at the same time or other non-drug related sources.
FDA Center for Veterinary Medicine publishes these words. Source: Adverse Event Reports for Animal Drugs and Devices, read on . The data have the reports that FDA received through .
This page is not veterinary advice. For an animal that is ill, speak to a veterinarian.
Contacting a veterinarianHow to report to FDAFDA reports received through . Counts include this ingredient alone and in combinations. Why brand names have no separate count.
From January 1988 to January 2026, FDA received 108 adverse event reports that name a drug with pyrethrins, alone or in a combination. 2 sets of active ingredients with pyrethrins have a drug page.
Of the 108 reports, 71 (65.7%) are about dogs. 36 reports are about cats (33.3%). In January to March 2026, FDA received 1 report that names pyrethrins, alone or in a combination. The signs that appear in the largest number of the 108 reports are "Lack of efficacy (ectoparasite) - flea" and "Lethargy". A report is not proof that a drug caused a sign.
Fewer than 20 reports named this ingredient in the 12 months before June 2026, so this page gives no change. Reports about cats are 33.3% of the reports that name this ingredient, and 11% of all reports.
Search engines list an ingredient page with 500 reports or more in all years. The page also needs 30 reports or more in the 12 months to June 2026. This page is under one of these numbers. The site keeps the page and keeps it out of search engines.
Reports in the latest closed quarter
| Species | Jan to Mar 2026 | Oct to Dec 2025 | Jan to Mar 2025 |
|---|---|---|---|
| All species | 1 | 1 | 1 |
| Dog | 0 | 0 | 1 |
| Cat | 1 | 1 | 0 |
| Horse | 0 | 0 | 0 |
| Other or not given | 0 | 0 | 0 |
January to March 2026 is the latest closed quarter in the data.
Drug pages with pyrethrins
A report names a drug by its set of active ingredients. Each set with pyrethrins that has a drug page is in the table, in order of name. The table has 2 sets.
| Active ingredients | Reports, all years | Reports, latest 12 months |
|---|---|---|
| Piperonyl Butoxide + Pyrethrins | 76 | 1 |
| Pyrethrins | 25 | 2 |
A report can name more than one set, so the counts of the sets can add to more than the count of the page.
An API dataset query result cannot be used to estimate the risk associated with the product or compare one drug or device product with another.
FDA Center for Veterinary Medicine. Source: Adverse Event Reports for Animal Drugs and Devices
Signs that the reports list
A sign is a coded term from the report. The words in brackets are a plain gloss of the term. The percentage is the share of the 108 reports that list the sign. One report can list more than one sign and more than one drug.
The sign that is in the largest number of the reports comes first.
- Lack of efficacy (ectoparasite) - flea[the product did not have the expected effect: fleas]35.2%38 reports
- Lethargy[unusually tired or inactive]14.8%16 reports
- Behavioural disorder NOS[behaviour change, type not specified]8.3%9 reports
- Lack of efficacy (flea)[the product did not have the expected effect: fleas]8.3%9 reports
- Vomiting8.3%9 reports
- Emesis[vomiting]7.4%8 reports
- Itching7.4%8 reports
- Lack of efficacy - NOS[the product did not have the expected effect]5.6%6 reports
- Diarrhoea[diarrhea]4.6%5 reports
- Anaemia NOS[low red blood cell count]3.7%4 reports
- Death by euthanasia[the animal was euthanized]3.7%4 reports
- Drooling3.7%4 reports
- Foaming at the mouth3.7%4 reports
- Hypersalivation[drooling]3.7%4 reports
Show the next 16 signs
- Pruritus[itching]3.7%4 reports
- Shaking3.7%4 reports
- Anaphylactoid reaction[sudden allergic-type reaction]2.8%3 reports
- Anorexia[not eating]2.8%3 reports
- Ataxia[unsteady, uncoordinated movement]2.8%3 reports
- Decreased appetite2.8%3 reports
- Dehydration2.8%3 reports
- Hiding2.8%3 reports
- Hyperactivity2.8%3 reports
- Seizure NOS[seizure, type not specified]2.8%3 reports
- Vocalisation[crying out or unusual noise]2.8%3 reports
- Abnormal radiograph finding1.9%2 reports
- Acting tense1.9%2 reports
- Adipsia[not drinking]1.9%2 reports
- Anxiety1.9%2 reports
- Application site inflammation[inflammation where the product was applied]1.9%2 reports
Reports by species
Reports for each month, Jul 2021 to Jun 2026
No chart: no month has 5 or more reports.
No chart: no month has 5 or more reports.
No chart: no month has 5 or more reports.
No chart: no month has 5 or more reports.
The month is the month in which FDA received the report. Each chart has its own scale. FDA says that a report can take 3 to 6 months to reach the public data. The newest months can get more reports in a later update.
Reports by year
- Dog
- Cat
- Horse
- Other or not given
| Year | Dog | Cat | Horse | Other or not given | All species |
|---|---|---|---|---|---|
| 2026 | 0 | 1 | 0 | 0 | 1 |
| 2025 | 3 | 3 | 0 | 0 | 6 |
| 2024 | 11 | 4 | 0 | 0 | 15 |
| 2023 | 6 | 8 | 0 | 0 | 14 |
| 2022 | 1 | 0 | 0 | 0 | 1 |
| 2021 | 4 | 2 | 0 | 0 | 6 |
| 2020 | 5 | 2 | 0 | 0 | 7 |
| 2019 | 2 | 1 | 0 | 0 | 3 |
| 2018 | 7 | 2 | 0 | 0 | 9 |
| 2017 | 1 | 3 | 0 | 0 | 4 |
| 2016 | 7 | 1 | 0 | 0 | 8 |
| 2015 | 1 | 2 | 0 | 0 | 3 |
| 2014 | 7 | 1 | 0 | 0 | 8 |
| 2013 | 10 | 1 | 0 | 1 | 12 |
| 2012 | 2 | 0 | 0 | 0 | 2 |
| 2011 | 3 | 0 | 0 | 0 | 3 |
| 2009 | 1 | 0 | 0 | 0 | 1 |
| 1999 | 0 | 2 | 0 | 0 | 2 |
| 1998 | 0 | 1 | 0 | 0 | 1 |
| 1990 | 0 | 1 | 0 | 0 | 1 |
| 1988 | 0 | 1 | 0 | 0 | 1 |
2026 has the reports that FDA received through Jan 2026. Download the years (CSV)
What the reports record
Outcome at the time of the report
- Recovered/Normal26.9%29
- Recovered with Sequela[recovered, with a lasting effect]0.9%1
- Ongoing15.7%17
- Died2.8%3
- Euthanized3.7%4
- Outcome Unknown46.3%50
An outcome in a report is not proof that the drug caused it. The person who sends the report gives the outcome. Each share is of the 108 reports that name pyrethrins.
Kind of report
- Safety issue60.2%65
- Lack of expected effectiveness18.5%20
- Both safety and lack of expected effectiveness14.8%16
- Manufacturing or product defect6.5%7
- Other0%0
Age of the animal
- Under 1 year13%14
- 1 to 3 years26.9%29
- 4 to 7 years22.2%24
- 8 to 11 years17.6%19
- 12 years and over5.6%6
- Age not given14.8%16
Each share of kind and age is of the 108 reports that name pyrethrins.
Approved animal drugs with this active ingredient (FDA Green Book)
This section is reference data. It has no report count.
The openFDA records give the value "MSK" for the brand name and for the manufacturer name of each drug. FDA says that MSK means "masked". So the site cannot count a report for a brand.
| Brand name | Active ingredients | Sponsor | Approved species | Application |
|---|---|---|---|---|
| Cerumiteapproval withdrawn | Piperonyl Butoxide, Pyrethrins, Squalene | Evsco Pharmaceuticals, An Affiliate of IGI, Inc. | Not in the list of major species | NADA 032-984 |
FDA pages for this ingredient
- How to Report Animal Drug and Device Side Effects and Product ProblemsThe FDA page that tells an owner or a veterinarian how to send a report.
- Animal Drugs @ FDAThe search page of the Green Book, the FDA list of approved animal drugs.
The site checked these addresses on . The links open in a new tab.
Cite this page
Pet Drug Reports. Pyrethrins, all combinations: adverse event reports that FDA received. https://petdrugreports.com/ingredient/pyrethrins/ Source: FDA Center for Veterinary Medicine, openFDA Animal and Veterinary adverse event reports, export of . Reports received through .
Where the data come from
The counts come from the openFDA Animal and Veterinary adverse event files, export of 30 Oct 2026. The files have the reports that the FDA Center for Veterinary Medicine received through 26 Jun 2026. The files mask brand and manufacturer names. The site counts a drug by the active ingredients that each record gives, and gives no count to a brand, an application or a company. Ingredient names and the lists of approved products follow the FDA Green Book of 2 Nov 2026. Ingredient names follow the Green Book, with salts and forms as FDA lists them.
The site does not publish report text, lot numbers or details of a reporter. FDA's record is the authority. See how the site counts reports, the data sources and the corrections page.
Questions about these reports
- Which brand are these reports about?
The openFDA records give the value "MSK" for the brand name and for the manufacturer name of each drug. FDA says that MSK means "masked". So the site cannot count a report for a brand. The Green Book lists no approved animal drug with this active ingredient.
- Do the reports show that the ingredient caused the signs?
No. A report can name more than one drug, and a drug can have more than one active ingredient. FDA states this about the data.
When looking at the results, be aware that there is no certainty that the reported drug or device caused the adverse event.
The adverse event may have been related to an underlying disease, other drugs used at the same time or other non-drug related sources.
FDA Center for Veterinary Medicine. Source: Adverse Event Reports for Animal Drugs and Devices
- How many reports did FDA receive in the latest 12 months?
FDA received 3 reports in the 12 months to June 2026. It received 15 reports in the 12 months before. FDA says that a report can take 3 to 6 months to reach the public data. The newest months can get more reports in a later update.
- What kinds of report are in the count?
Of the 108 reports received from January 1988 to January 2026, 60.2% are about a safety issue only. 33.3% are about a lack of expected effectiveness, alone or with a safety issue. 6.5% are about a defect of the product or its package.