Pet Drug Reports

Reported signs

Reported sign · VeDDRA term

Hair shedding: reports listing this term

1,155reports listing the term, 1997–20260.1% of all reports
35reports, 12 months to March 202637 in the 12 months before
40.7%classed serious, as reportedall reports: 38.6%
86.5%of these reports concern dogscat 11.6%

"Hair shedding" is a coded term listed in 1,155 adverse event reports received by FDA, 0.1% of the database. Terms come from VeDDRA, the veterinary dictionary that FDA and drug companies use to code what a reporter describes.

35 reports listed it in the 12 months to March 2026, close to the 37 of 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.

By active ingredient, the drugs named most often in those reports are cyclosporine, carprofen and afoxolaner. That order mostly follows how many reports each has overall; the table gives the term's share within each drug's own reports as well.

86.5% of the reports concern dogs, 11.6% of the reports concern cats and 1% of the reports concern cattle. Of reports listing this term that state seriousness, 40.7% were classed as serious; 2.6% record a death or euthanasia among the outcomes.

Drugs named most often in these reports, by active ingredient

Active ingredients recorded for the drugReports listing the termShare of that drug's own reports
Cyclosporine1970.9%
Carprofen1130.2%
Afoxolaner930.2%
Milbemycin Oxime + Spinosad870.1%
Selamectin750.1%
Fluralaner650.1%
Oclacitinib500.2%
Spinosad500.1%
Ivermectin + Pyrantel Pamoate480%
Trilostane330.3%
Bedinvetmab310.2%
Imidacloprid + Moxidectin250.1%
Prednisone250.3%
Lufenuron + Milbemycin Oxime240.1%
Desoxycorticosterone Pivalate220.9%
Levothyroxine sodium220.7%
Moxidectin210%
Melarsomine Dihydrochloride170.1%
Deracoxib160.1%
Meloxicam160.1%
Pyrantel Pamoate + Sarolaner160%
Ketoconazole150.6%
Sarolaner130.1%
Firocoxib120.1%
Milbemycin Oxime120%

Ordered by number of reports, which mostly tracks how many reports a drug has overall. Across the whole database the term appears in 0.1% of reports. A drug's presence in a report means the animal received it, not that it produced the sign; FDA states that these data cannot be used to compare one product with another. openFDA masks brand and manufacturer names in adverse event records, so the reports counted here cannot be attributed to a particular brand.

Single ingredients, pooled across combinations

Active ingredientReports listing the termShare of the ingredient's own reports
Cyclosporine1970.9%
Spinosad1370.1%
Milbemycin Oxime1310.1%
Carprofen1130.2%
Afoxolaner960.1%
Selamectin800.1%
Pyrantel Pamoate770%
Fluralaner730.1%
Moxidectin650.1%
Ivermectin560%
Oclacitinib500.2%
Sarolaner380%
Praziquantel330%
Trilostane330.3%
Imidacloprid320.1%
Bedinvetmab310.2%
Lufenuron310.1%
Prednisone250.3%
Desoxycorticosterone Pivalate220.9%
Levothyroxine sodium220.7%
Melarsomine Dihydrochloride170.1%
Deracoxib160.1%
Meloxicam160.1%
Ketoconazole150.6%
Prednisolone150.3%

Species split

Dog86.5%999
Cat11.6%134
Cattle1%12
Horse0.6%7
Rabbit0.1%1
Sheep0.1%1

Coloured bar: share of reports listing this term. Grey bar: the species' share of all reports. The term appears in 0.1% of all dog reports; The term appears in 0.1% of all cat reports.

Trend

036Apr 2021: 6May 2021: 0Jun 2021: 4Jul 2021: 6Aug 2021: 0Sep 2021: 6Oct 2021: 4Nov 2021: 0Dec 2021: 4Jan 2022: 12022Feb 2022: 2Mar 2022: 3Apr 2022: 1May 2022: 3Jun 2022: 2Jul 2022: 5Aug 2022: 3Sep 2022: 0Oct 2022: 0Nov 2022: 4Dec 2022: 5Jan 2023: 32023Feb 2023: 3Mar 2023: 2Apr 2023: 2May 2023: 3Jun 2023: 3Jul 2023: 4Aug 2023: 3Sep 2023: 2Oct 2023: 0Nov 2023: 4Dec 2023: 2Jan 2024: 62024Feb 2024: 6Mar 2024: 4Apr 2024: 4May 2024: 1Jun 2024: 1Jul 2024: 2Aug 2024: 4Sep 2024: 4Oct 2024: 5Nov 2024: 2Dec 2024: 4Jan 2025: 52025Feb 2025: 3Mar 2025: 2Apr 2025: 2May 2025: 1Jun 2025: 1Jul 2025: 2Aug 2025: 5Sep 2025: 3Oct 2025: 2Nov 2025: 1Dec 2025: 4Jan 2026: 52026Feb 2026: 5Mar 2026: 4

Reports by month FDA received them, five years to March 2026. The newest months are incomplete because FDA posts reports with a delay of three to six months.

039771997: 119971998: 131999: 262000: 3620002001: 232002: 162003: 2220032004: 342005: 452006: 2820062007: 332008: 452009: 4620092010: 582011: 482012: 5920122013: 582014: 672015: 7720152016: 712017: 512018: 4920182019: 312020: 352021: 3520212022: 292023: 312024: 4320242025: 312026: 14

Outcomes and ages in these reports

Outcome recorded in the report

Recovered/Normal8.1%94
Recovered with Sequela4.1%47
Ongoing21.3%246
Died1.5%17
Euthanized1.1%13
Outcome Unknown24.2%279

Age of the animal

Under 1 year6%69
1 to 3 years23.7%274
4 to 7 years27.3%315
8 to 11 years23.6%273
12 years and over13%150
Age not given6.4%74
MeasureReports listing this termAll reports
Reports1,1551,357,245
Classed serious, of reports stating it40.7%38.6%
Death or euthanasia recorded, per 1,000 reports2663.8

Grey bars and the right-hand column are the whole database. Outcomes are as stated by the reporter and describe the report as a whole, not this term alone.

Questions about "Hair shedding"

What does "Hair shedding" mean in an adverse event report?

It is a VeDDRA dictionary term picked to code what the reporter described. The report's free-text description is not published by FDA and is not shown here.

How many reports list hair shedding?

1,155 reports through March 2026 (0.1% of all reports), 35 of them in the latest 12 months.

Which drugs are named most often alongside this term?

By active ingredient: cyclosporine (197), carprofen (113), afoxolaner (93), milbemycin oxime + spinosad (87) and selamectin (75). Drugs with many reports overall lead almost every term's list. Brands cannot be identified: openFDA masks them.

Which species are involved?

dog (86.5%), cat (11.6%), cattle (1%) and horse (0.6%).

Does a drug appearing here mean it produced this sign?

No such conclusion can be drawn. 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."

My animal shows this sign. What now?

This site cannot assess an animal. A veterinarian can; for an emergency, contact a veterinary emergency clinic. See the guide on when to call a vet.

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 1 Oct 2026. Spelling variants of the same VeDDRA term (for example with and without a cross-reference note) are pooled. 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.