Alopecia NOS: in adverse event reports for animal drugs

Clinical sign, a VeDDRA term

In plain words: hair loss, type not specified.

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 2 Oct 2026. The data have the reports that FDA received through 26 Jun 2026.

This page is not veterinary advice. For an animal that is ill, speak to a veterinarian.

Contacting a veterinarian How to report to FDA

From February 1987 to June 2026, FDA received 4,260 adverse event reports for animal drugs that list this sign. That is 0.3% of the 1,378,761 reports that FDA received from January 1987 to June 2026. In the 12 months to June 2026, FDA received 34 reports that list this sign.

Of the 4,260 reports, 58.8% are about dogs. A report can list more than one sign and more than one drug. A report is not proof that a drug caused a sign.

By number of reports in all years, this sign is number 153 of 1,149 clinical signs with a page. Fewer than 20 reports listed this sign in the 12 months before June 2026, so this page gives no change. Reports about cattle are 17.6% of the reports that list this sign, and 2.3% of all reports.

Search engines list a sign page with 3,000 reports or more in all years. The page also needs 300 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.

Drug pages with reports that list this sign

The table has every drug page with 20 or more reports that list this sign, in order of name. No count decides which drug is in the table. The table has 36 drug pages.

Show the 36 drug pages

Drug pages with 20 or more reports that list this sign, in order of name
Active ingredients	Reports that list the sign
(S) - methoprene	42
Afoxolaner	91
Amoxicillin	56
Carprofen	310
Cefovecin sodium	83
Cefpodoxime proxetil	21
Cyclosporine	219
Deracoxib	41
Desoxycorticosterone Pivalate	55
Dirlotapide	35
Doramectin	407
Emodepside + Praziquantel	36
Enrofloxacin	25
Eprinomectin	53
Firocoxib	33
Fluralaner	29
Imidacloprid + Moxidectin	162
Insulin	43
Ivermectin	211
Ivermectin + Pyrantel Pamoate	89
Levamisole	23
Lufenuron	82
Lufenuron + Milbemycin Oxime	108
Melarsomine Dihydrochloride	59
Meloxicam	55
Methylprednisolone Acetate	26
Milbemycin Oxime	85
Milbemycin Oxime + Spinosad	82
Moxidectin	180
Nitenpyram	30
Oclacitinib	59
Prednisone	33
Selamectin	829
Selegiline Hydrochloride	39
Spinosad	213
Tepoxalin	25

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. A report can name more than one drug.

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.
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

Ingredients, all combinations

The list has every active ingredient with 20 or more reports that list this sign, in order of name. It has 37 ingredients.

Show the 37 ingredients

Reports by species

Dog58.8%2,507
Cat20.7%883
Cattle17.6%751
Horse1.7%74
Human exposure0.4%16
Rabbit0.2%7

The share is of the 4,260 reports that list this sign. The sign is in 0.3% of all reports about the species dog. The sign is in 0.6% of all reports about the species cat.

Reports by month and by year

Reports for each month, Jul 2021 to Jun 2026. The month is the month in which FDA received the report.

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 that list Alopecia NOS, by the year in which FDA received them
Year	Reports
2026	14
2025	26
2024	34
2023	14
2022	17
2021	16
2020	19
2019	28
2018	30
2017	60
2016	78
2015	103
2014	69
2013	116
2012	166
2011	243
2010	363
2009	442
2008	331
2007	260
2006	167
2005	188
2004	191
2003	96
2002	138
2001	189
2000	381
1999	110
1998	221
1997	42
1996	34
1995	10
1994	7
1993	9
1992	6
1991	7
1990	13
1989	7
1988	6
1987	9

What these reports record

Outcome at the time of the report

Reports with this sign
All reports

Recovered/Normal2.5%107, All reports: 20.7%
Recovered with Sequela[recovered, with a lasting effect]0.8%34, All reports: 2.3%
Ongoing4.8%205, All reports: 17.4%
Died3%127, All reports: 4.9%
Euthanized0.4%19, All reports: 1.5%
Outcome Unknown7.9%336, All reports: 22.7%

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 4,260 reports that list this sign.

Age of the animal

Reports with this sign
All reports

Under 1 year11.4%487, All reports: 9.5%
1 to 3 years21.1%897, All reports: 23.9%
4 to 7 years22.7%966, All reports: 20.2%
8 to 11 years17.2%733, All reports: 15.4%
12 years and over11.4%486, All reports: 10.7%
Age not given16.2%691, All reports: 20.3%

The outcome is for the full report, not for this sign only.

Next in the A to Z list of signs

Allergy NOS[NOS: not otherwise specified]
Alopecia[hair loss]
Alopecia general
Alopecia local
Alteration of milk quality
Anaemia NOS[low red blood cell count]
Anal and rectal disorder NOS[NOS: not otherwise specified]
Anal irritation

All clinical signs

Cite this page

Pet Drug Reports. Alopecia NOS: adverse event reports for animal drugs. https://petdrugreports.com/reaction/alopecia-nos/ Source: FDA Center for Veterinary Medicine, openFDA Animal and Veterinary adverse event reports, export of 30 Oct 2026. Reports received through 26 Jun 2026.

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. The site counts the different spellings of one VeDDRA term together.

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 this sign

What does this term mean in a report?: In plain words: hair loss, type not specified. It is a term from VeDDRA, the list of terms that FDA and drug companies use to code a report. The person who coded the report selected the term.
How does the count of the latest 12 months compare with the 12 months before?: FDA received 34 reports in the 12 months to June 2026. It received 14 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.
How many of these reports have a serious flag?: Of the 690 reports that say if the event was serious, 51.6% have the serious flag. The person who sends a report sets the flag.
Does a drug in the table cause this sign?: The reports do not show that. A report can name more than one drug. 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