Reaction profile

The FDA adverse-event record for mydriasis

1,997 FDA reports name mydriasis, a high-volume reaction in the CVM extract (VeDDRA 690). Plate stamps and neighbourhood peers follow.

#234 of 2,481
by report volume (all reactions)
1,997
reports citing this reaction
12.9%
death-coded share
Dog
most-affected species

Release-over-release change

What changed in the latest FDA data snapshot

PlainBreed reconstructed the prior snapshot from dated openFDA partitions through 2025 Q4, then compared it with the 2026-07-27 openFDA export. Mydriasis has 1,997 reports now versus 1,981 in that prior snapshot: 16 more (0.8%).

Report change
+16
Death-coded reports
+3
Death-coded share
+0.0 pts

This compares reported-event counts in two source snapshots. It does not establish a change in real-world risk, product safety, or disease incidence.

Subscribe to Mydriasis changes

FDA AER · VeDDRA plate

Code 690 VOL-MID

VOL-MID · DEATH-ELEV · TOP-DECILE · PHOTO-FINISH · SPECIES-DOG · DRUG-LEAD · DESK-WIDE · BOOK-FULL

  • VOL-MID 1,997 reports
  • DEATH-ELEV 12.9%
  • TOP-DECILE #234/2481
  • PHOTO-FINISH Hind limb ataxia
  • SPECIES-DOG Dog · 1,162
  • DRUG-LEAD Ivermectin · 210
  • DESK-WIDE 20 breeds
  • BOOK-FULL 8/8 fields

Nearest volume peer: Hind limb ataxia (±2 reports)

Upper-third report volume drives the scale stamps on this plate; death-coded share and co-report peers follow. Not a clinical diagnosis.

High-volume neighbourhood around Mydriasis

Upper-third volume poles plus nearest peers, not a full reaction corpus board reprint.

Vomiting · highest174348INEFFECTIVE, WHIPS · near2007Abnormal cytology · near2004Cardiac arrest · near2003Hind limb ataxia · near1999Mydriasis · this reaction1997Urinary tract neoplas… · low…10
FDA AER report volume · neighbourhood around Mydriasis

What the FDA AER plate says about Mydriasis

Signature read: 258 death-coded reports is a heavy tail count for Mydriasis in the CVM extract. Report volume is upper-third scale: 1,997 named reports in the openFDA extract. 258 of 1,997 reports were death-coded (12.9% of named reports, not a population mortality rate). Nearest volume peer: Hind limb ataxia (±2 reports). Lead species Dog (1,162). Lead co-reported drug Ivermectin (210).

Read these counts as reporting volume, not risk: per our methodology, Lead co-reported drug Ivermectin appears in filings alongside this reaction; that is association, not causation. Browse the full reactions index or the about page for how PlainBreed frames FDA CVM extracts.

Species Most Affected

Dog 1,162
Cat 813
Human 7
Cattle 7
Rabbit 2
Horse 2
Sheep 1
Pig 1
Other Birds 1
Parrot 1

Breeds Most Affected

Domestic Shorthair 383
Domestic (unspecified) 190
Retriever - Labrador 129
Crossbred Canine/dog 120
Chihuahua 70
Cat (unknown) 62
Domestic Longhair 42
Pit Bull 41
Shepherd Dog - Australian 38
Boxer (German Boxer) 36

Associated Drugs

Ivermectin 210
Buprenorphine 156
Spinosad 150
Imidacloprid + Moxidectin 147
Milbemycin Oxime + Spinosad 112
Phenylpropanolamine Hcl 91
Enrofloxacin 71
Maropitant Citrate 55
Cefovecin Sodium 53
Emodepside + Praziquantel 49
Selamectin 46
Ivermectin + Pyrantel As Pamoate Salt 46
Isoflurane 45
Afoxolaner 44
Nitenpyram 41
Robenacoxib 38
Fluralaner Chew Tablets 38
Cefovecin 36
Ketamine 31
Propofol 29

Nationwide reactions with similar profiles

Two openFDA-derived peer sets for Mydriasis, both floored at ≥50 reports so the neighborhoods stay in the advertised mass (the volume chart above is the unfloored photo-finish strip).

Similar report volume

Nearest other reactions by FDA report count (1,997 here).

Similar death-coded share

Nearest other reactions by death-coded share (12.9% here), distinct from the volume row.

What to do with this reaction

A report does not prove a drug caused the reaction; consult a veterinarian before acting on this data.

Source: FDA Center for Veterinary Medicine openFDA Animal & Veterinary Adverse Events (CVM AER) · 2025

openFDA Animal & Veterinary Adverse Events (FDA CVM) for Mydriasis (#234 of 2,481 by report volume); death-coded 12.9%. PlainBreed reaction plate · death-coded report count stamp 258 · vintage 2025.

Informational only. FDA adverse-event reports are voluntary and do not prove causation; consult a veterinarian before acting on them. Verify with FDA CVM →