April 2000: adverse event reports received

1,170 reports in the openFDA release of 28 Sep 2026

Read this first · FDA's caveat, in its words

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

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Not veterinary advice. This site lists what was reported to FDA. For an animal that is unwell, contact a veterinarian.

1,170reports received

778same month a year earlier+50%

1,081monthly average, preceding 12 months

68.4%concern dogscats 10.8%

FDA's database holds 1,170 adverse event reports received in April 2000, against 778 in the same month a year earlier and a monthly average of 1,081 over the preceding 12 months.

68.4% of the month's reports concern dogs, 10.8% cats and 3.4% horses; the rest concern other species, exposed people, or give no species.

By active ingredient, the drugs named most often were carprofen (482), selamectin (236) and milbemycin oxime (41), and the terms listed most often were accidental exposure (233), vomiting (194) and no sign (151). Report volume has a seasonal shape, with more reports in the warmer months when parasite products are in heavier use.

The months around it

Drugs named most often, by active ingredient

Active ingredients recorded for the drug	Reports	Share of the month's reports
Carprofen	482	41.2%
Selamectin	236	20.2%
Milbemycin Oxime	41	3.5%
Selegiline Hydrochloride	36	3.1%
Pyrantel Tartrate	31	2.6%
Lufenuron + Milbemycin Oxime	29	2.5%
Amoxicillin	28	2.4%
Etodolac	25	2.1%
Tilmicosin Phosphate	24	2.1%
Oxibendazole	15	1.3%
Melarsomine Dihydrochloride	14	1.2%
Moxidectin	12	1%
Enrofloxacin	11	0.9%
Amitraz	10	0.9%
Medetomidine	10	0.9%

Ordered by report count, which follows how widely each drug was in use. FDA states that these data cannot be used to estimate risk or to compare one product with another. Brand and manufacturer names are masked by FDA in these records.

Signs listed most often

Accidental exposure[exposure that was not intended]19.9%233
Vomiting16.6%194
No sign[no clinical sign was reported]12.9%151
Depression[dull, quiet or withdrawn]12.2%143
Anorexia[not eating]11.9%139
Elevated serum alkaline phosphatase (SAP)[a liver and bone enzyme above the normal range]9.5%111
Elevated alanine aminotransferase (ALT)[a liver enzyme above the normal range]8.9%104
Death7.9%92
Unclassifiable adverse event[event that fits no dictionary term]6.7%78
Diarrhoea[diarrhea]6.6%77
Elevated total bilirubin[bilirubin above the normal range]5%58
Death by euthanasia[the animal was euthanized]3.7%43
Ataxia[unsteady, uncoordinated movement]3.6%42
Convulsion[seizure]3.2%38
Pruritus[itching]3.2%38

Single ingredients, pooled

Carprofen41.2%482

Selamectin20.2%236

Milbemycin Oxime6%70

Lufenuron3.1%36

Selegiline Hydrochloride3.1%36

Pyrantel Tartrate2.6%31

Amoxicillin2.4%28

Etodolac2.1%25

Tilmicosin Phosphate2.1%24

Oxibendazole1.3%15

Melarsomine Dihydrochloride1.2%14

Ivermectin1%12

Species

Dog68.4%800

Cat10.8%126

Horse3.4%40

Other or not given17.4%204

Questions about April 2000

How many animal drug adverse event reports did FDA receive in April 2000?

1,170 reports are in the openFDA release of 28 Sep 2026. The same month a year earlier has 778.

Which drugs were named most often?

By active ingredient: carprofen (482), selamectin (236), milbemycin oxime (41), selegiline hydrochloride (36) and pyrantel tartrate (31). Brands are masked in the public data.

Which signs were listed most often?

accidental exposure (233), vomiting (194), no sign (151), depression (143) and anorexia (139).

Can the count for a month still change?

Yes. FDA posts reports quarterly with a delay of three to six months, so the newest months are incomplete and usually grow in later releases. Older months change little.

Does a busy month mean something went wrong that month?

Not by itself. The date is when FDA received the report, not when the event happened, and volume follows season, product launches and publicity. 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."

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. The month is the date FDA first received the report, not the date of the event. 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.