May 2026: adverse event reports that FDA received

Month in which FDA received the reports

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.

FDA received 6,510 adverse event reports for animal drugs in May 2026. It received 7,372 reports in May 2025. The average of the 12 months before May 2026 is 6,512 reports for each month.

Of the 6,510 reports, 75.6% are about dogs, 14.7% are about cats and 1.2% are about horses. The other reports are about other species, or give no species. A report is not proof that a drug caused a sign.

Search engines do not list month pages. The site keeps the page, and the list of months links it.

The months before and after

Reports for each month, Nov 2024 to Jun 2026. The column with the outline is May 2026.

Reports by species

Dog75.6%4,922
Cat14.7%955
Horse1.2%75
Other species, or species not given8.6%558

Drug pages with reports received in May 2026

The table has every drug page with 10 or more reports that FDA received in May 2026, in order of name. No count decides which drug is in the table. The table has 97 drug pages.

Show the 97 drug pages

Drug pages with 10 or more reports received in May 2026, in order of name
Active ingredients	Reports received in May 2026
Afoxolaner	240
Afoxolaner + Moxidectin + Pyrantel Pamoate	392
Amantadine	12
Amlodipine	11
Amoxicillin	16
Amoxicillin + Clavulanate Potassium	22
Amoxicillin Trihydrate + Clavulanate Potassium	26
Atinvicitinib	179
Atipamezole Hydrochloride	18
Bedinvetmab	300
Benazepril	14
Bexagliflozin	101
Buprenorphine	63
Butorphanol Tartrate	47
Capromorelin	41
Carprofen	157
Cefovecin sodium	54
Cefpodoxime proxetil	27
Clindamycin	14
Cyclosporine	53
Deracoxib	11
Dexamethasone	26
Dexamethasone Sodium Phosphate	10
Dexmedetomidine	24
Dexmedetomidine hydrochloride	22
Diphenhydramine	42
Doxycycline	54
Emodepside + Praziquantel	14
Enrofloxacin	26
Eprinomectin + Esafoxolaner + Praziquantel	69
Estriol	21
Famotidine	28
Febantel + Praziquantel + Pyrantel Pamoate	41
Fenbendazole	14
Florfenicol + Mometasone furoate + Terbinafine	31
Fluoxetine hydrochloride	27
Fluralaner	1,124
Fluralaner + Moxidectin	53
Frunevetmab	130
Furosemide	25
Gabapentin	178
Grapiprant	87
Ilunocitinib	138
Imidacloprid	41
Imidacloprid + Moxidectin	46
Insulin	48
Isoflurane	46
Ivermectin	14
Ivermectin + Pyrantel Pamoate	350
Ketamine Hydrochloride	20
Ketoconazole	22
Levetiracetam	13
Levothyroxine sodium	18
Lotilaner	131
Lotilaner + Moxidectin + Praziquantel + Pyrantel Pamoate	365
Lufenuron + Milbemycin Oxime	28
Lufenuron + Milbemycin Oxime + Praziquantel	64
Maropitant	174
Melarsomine Dihydrochloride	59
Meloxicam	35
Methimazole	23
Methocarbamol	10
Metronidazole	41
Midazolam	16
Milbemycin Oxime	26
Milbemycin Oxime + Praziquantel	168
Milbemycin Oxime + Spinosad	55
Mirtazapine	89
Monensin	10
Moxidectin	338
Moxidectin + Pyrantel Pamoate + Sarolaner	23
Neomycin Sulfate + Nystatin + Thiostrepton + Triamcinolone Acetonide	18
Nitenpyram	103
Oclacitinib	204
Omeprazole	48
Ondansetron	20
Pergolide mesylate	14
Phenobarbital	14
Phenylpropanolamine hydrochloride	18
Pimobendan	65
Polysulfated Glycosaminoglycan	20
Praziquantel	17
Prednisolone	36
Prednisone	79
Propofol	41
Pyrantel Pamoate + Sarolaner	876
Robenacoxib	23
Sarolaner	71
Sarolaner + Selamectin	118
Selamectin	72
Sodium Chloride	36
Sucralfate	38
Tigilanol tiglate	14
Trazodone	32
Trilostane	59
Ursodiol	11
Velagliflozin	152

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.

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.
Commonly used products may have a higher number of reported adverse events due to the higher total number of animals being given the product.
FDA Center for Veterinary Medicine. Source: Adverse Event Reports for Animal Drugs and Devices

Signs that the reports of the month 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 6,510 reports of the month.

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]11.7%761 reports
Vomiting10.6%689 reports
Lethargy[unusually tired or inactive]8.2%537 reports
Lack of efficacy - NOS[the product did not have the expected effect]6.4%418 reports
Diarrhoea[diarrhea]6%388 reports
Lack of efficacy (endoparasite) - heartworm[the product did not have the expected effect: heartworm]5.5%361 reports
Lack of efficacy (endoparasite) - hookworm[the product did not have the expected effect: hookworms]5.2%341 reports
Medication error NOS[a mistake in giving the product, type not specified]4.1%269 reports
Seizure NOS[seizure, type not specified]4%259 reports
Lack of efficacy (ectoparasite) - tick NOS[the product did not have the expected effect: ticks]3.9%254 reports
Not eating3.3%218 reports
Lack of efficacy (bacteria) - Borrelia[the product did not have the expected effect: Borrelia (Lyme disease bacteria)]3.3%215 reports
Lack of efficacy (bacteria) - Anaplasma[the product did not have the expected effect: Anaplasma bacteria]3.3%214 reports
Intentional misuse[use that was knowingly different from the label]3%198 reports

Show the next 1 signs

Emesis (multiple)[vomiting more than once]3%196 reports

Ingredients, all combinations

The list has every active ingredient with 10 or more reports received in May 2026, in order of name. It has 98 ingredients.

Show the 98 ingredients

The same month in other years

Cite this page

Pet Drug Reports. May 2026: adverse event reports for animal drugs. https://petdrugreports.com/month/2026-05/ 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 month is the month in which FDA received the report, not the month of the event.

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 month

Can the count for May 2026 change?: Yes. 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.
Does the month show when the event occurred?: No. The month is the month in which FDA received the report. The event can be from an earlier month.
Which sign is in the largest number of the reports of the month?: "Lack of efficacy (ectoparasite) - flea" is in 761 reports of the 6,510 reports of May 2026 (11.7%).