Pet Drug Reports

Reported signs

Reported sign · VeDDRA term

Localised hair loss: reports listing this term

1,713reports listing the term, 2006–20260.1% of all reports
189reports, 12 months to March 2026214 in the 12 months before
42.9%classed serious, as reportedall reports: 38.6%
55.5%of these reports concern dogscat 36.8%

"Localised hair loss" is a coded term listed in 1,713 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.

189 reports listed it in the 12 months to March 2026, down 12% from 214 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.

By active ingredient, the drugs named most often in those reports are fluralaner, frunevetmab and milbemycin oxime + spinosad. 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.

55.5% of the reports concern dogs, 36.8% of the reports concern cats and 5.3% of the reports concern cattle. Of reports listing this term that state seriousness, 42.9% were classed as serious; 2.9% 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
Fluralaner2230.3%
Frunevetmab1952.5%
Milbemycin Oxime + Spinosad1390.1%
Afoxolaner1260.2%
Selamectin960.2%
Ivermectin + Pyrantel Pamoate770%
Oclacitinib750.3%
Sarolaner + Selamectin730.8%
Cefovecin sodium530.4%
Spinosad500.1%
Fluralaner + Moxidectin481.3%
Ivermectin480.2%
Prednisone460.5%
Trilostane450.4%
Imidacloprid + Moxidectin430.2%
Pyrantel Pamoate + Sarolaner430.1%
Bedinvetmab420.2%
Gabapentin390.4%
Nitenpyram310.1%
Carprofen290.1%
Doramectin280.6%
Cyclosporine270.1%
(S) - methoprene270.4%
Insulin230.2%
Maropitant230.1%

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
Fluralaner2700.3%
Frunevetmab1952.5%
Milbemycin Oxime1910.1%
Spinosad1860.1%
Selamectin1670.2%
Pyrantel Pamoate1640.1%
Afoxolaner1430.2%
Moxidectin1380.1%
Sarolaner1340.2%
Ivermectin1320.1%
Praziquantel820.1%
Oclacitinib750.3%
Imidacloprid550.2%
Cefovecin sodium530.4%
Prednisone460.5%
Trilostane450.4%
Bedinvetmab420.2%
Gabapentin390.4%
Eprinomectin330.5%
Lufenuron330.1%
Nitenpyram310.1%
Carprofen290.1%
Doramectin280.6%
Cyclosporine270.1%
Dexamethasone270.5%

Species split

Dog55.5%951
Cat36.8%631
Cattle5.3%90
Horse1.7%29
Human exposure0.3%5
Ferret0.2%3

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 0.4% of all cat reports.

Trend

01224Apr 2021: 8May 2021: 11Jun 2021: 8Jul 2021: 10Aug 2021: 8Sep 2021: 7Oct 2021: 13Nov 2021: 5Dec 2021: 4Jan 2022: 32022Feb 2022: 6Mar 2022: 8Apr 2022: 6May 2022: 12Jun 2022: 10Jul 2022: 9Aug 2022: 8Sep 2022: 10Oct 2022: 9Nov 2022: 10Dec 2022: 10Jan 2023: 122023Feb 2023: 14Mar 2023: 7Apr 2023: 11May 2023: 15Jun 2023: 12Jul 2023: 9Aug 2023: 20Sep 2023: 15Oct 2023: 9Nov 2023: 21Dec 2023: 8Jan 2024: 132024Feb 2024: 15Mar 2024: 20Apr 2024: 19May 2024: 18Jun 2024: 22Jul 2024: 24Aug 2024: 24Sep 2024: 22Oct 2024: 20Nov 2024: 15Dec 2024: 11Jan 2025: 152025Feb 2025: 12Mar 2025: 12Apr 2025: 23May 2025: 21Jun 2025: 16Jul 2025: 14Aug 2025: 14Sep 2025: 22Oct 2025: 21Nov 2025: 10Dec 2025: 12Jan 2026: 92026Feb 2026: 15Mar 2026: 12

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.

01122232006: 220062011: 182012: 6620122013: 692014: 8820142015: 1262016: 11320162017: 1072018: 10920182019: 942020: 11320202021: 1032022: 10120222023: 1532024: 22320242025: 1922026: 362026

Outcomes and ages in these reports

Outcome recorded in the report

Recovered/Normal10.9%186
Recovered with Sequela4.7%80
Ongoing46.5%796
Died0.8%13
Euthanized2.1%36
Outcome Unknown35.3%605

Age of the animal

Under 1 year8.3%142
1 to 3 years21.9%375
4 to 7 years22.8%390
8 to 11 years19.5%334
12 years and over20.5%352
Age not given7%120
MeasureReports listing this termAll reports
Reports1,7131,357,245
Classed serious, of reports stating it42.9%38.6%
Death or euthanasia recorded, per 1,000 reports28.663.8

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 "Localised hair loss"

What does "Localised hair loss" 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 localised hair loss?

1,713 reports through March 2026 (0.1% of all reports), 189 of them in the latest 12 months.

Which drugs are named most often alongside this term?

By active ingredient: fluralaner (223), frunevetmab (195), milbemycin oxime + spinosad (139), afoxolaner (126) and selamectin (96). Drugs with many reports overall lead almost every term's list. Brands cannot be identified: openFDA masks them.

Which species are involved?

dog (55.5%), cat (36.8%), cattle (5.3%) and horse (1.7%).

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.