Reaction profile

The FDA adverse-event record for arrhythmia

918 FDA reports name arrhythmia, a high-volume reaction in the CVM extract (VeDDRA 186). Plate stamps and neighbourhood peers follow.

#421 of 2,481
by report volume (all reactions)
918
reports citing this reaction
24.6%
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. Arrhythmia has 918 reports now versus 903 in that prior snapshot: 15 more (1.7%).

Report change
+15
Death-coded reports
+4
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 Arrhythmia changes

FDA AER · VeDDRA plate

Code 186 VOL-MID

VOL-MID · DEATH-HOT · UPPER-Q · PHOTO-FINISH · SPECIES-DOG · DRUG-LEAD · DESK-WIDE · BOOK-FULL

  • VOL-MID 918 reports
  • DEATH-HOT 24.6%
  • UPPER-Q #421/2481
  • PHOTO-FINISH Abnormal adrenocortic…
  • SPECIES-DOG Dog · 692
  • DRUG-LEAD Dexmedetomidine H… · 85
  • DESK-WIDE 20 breeds
  • BOOK-FULL 8/8 fields

Nearest volume peer: Abnormal adrenocorticotropic hormone (ACTH) stimulation test (±2 reports)

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

High-volume neighbourhood around Arrhythmia

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

Vomiting · highest174348Reduced responses · near924Knuckling · near923Abnormal adrenocortic… · near920Arrhythmia · this reaction918Application site burn · near911Urinary tract neoplas… · low…10
FDA AER report volume · neighbourhood around Arrhythmia

Arrhythmia: high death-coded share in the FDA AER plate

Signature read: 226 death-coded reports is a heavy tail count for Arrhythmia in the CVM extract. Report volume is upper-third scale: 918 named reports in the openFDA extract. Death-coded share is upper-third: 226 of 918 reports (24.6% of named reports). Nearest volume peer: Abnormal adrenocorticotropic hormone (ACTH) stimulation test (±2 reports). Lead species Dog (692). Lead co-reported drug Dexmedetomidine Hydrochloride (85).

Read these counts as reporting volume, not risk: per our methodology, A high death-coded share in FDA filings does not prove causation; co-reporting is voluntary temporal association only. Browse the full reactions index or the about page for how PlainBreed frames FDA CVM extracts.

Species Most Affected

Dog 692
Cat 191
Horse 16
Human 11
Cattle 3
Rabbit 3
Monkey 1
Jaguar 1

Breeds Most Affected

Domestic Shorthair 103
Retriever - Labrador 71
Crossbred Canine/dog 55
Boxer (German Boxer) 40
Dog (unknown) 31
Shepherd Dog - German 26
Chihuahua 25
Domestic (unspecified) 24
Retriever - Golden 23
Unknown 22

Associated Drugs

Dexmedetomidine Hydrochloride 85
Carprofen 72
Maropitant Citrate 65
Pimobendan 62
Milbemycin Oxime + Spinosad 55
Isoflurane 50
Gabapentin 50
Bedinvetmab 49
Propofol 48
Butorphanol 47
Cefovecin 38
Moxidectin 37
Trilostane 33
Oclacitinib Maleate 33
Buprenorphine 28
Spinosad 26
Ketamine 26
Prednisone 25
Atipamezole Hydrochloride 22
Dexmedetomidine 22

Nationwide reactions with similar profiles

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

Similar death-coded share

Nearest other reactions by death-coded share (24.6% 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 Arrhythmia (#421 of 2,481 by report volume); death-coded 24.6%. PlainBreed reaction plate · death-coded report count stamp 226 · 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 →