Reaction profile

The FDA adverse-event record for asystole

42 FDA reports name asystole, a lower-volume reaction in the CVM extract (VeDDRA 2840). Plate stamps and neighbourhood peers follow.

#1824 of 2,481
by report volume (all reactions)
42
reports citing this reaction
81.0%
death-coded share
Dog
most-affected species
Verify with FDA CVM →

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. Asystole has 42 reports now versus 41 in that prior snapshot: 1 more (2.4%).

Report change
+1
Death-coded reports
+1
Death-coded share
+0.5 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 Asystole changes

FDA AER · VeDDRA plate

Code 2840 VOL-TRACE

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

  • VOL-TRACE 42 reports
  • DEATH-HOT 81.0%
  • MID-PACK #1824/2481
  • PHOTO-FINISH Allergy to food
  • SPECIES-DOG Dog · 29
  • DRUG-LEAD Butorphanol · 11
  • DESK-WIDE 20 breeds
  • BOOK-FULL 8/8 fields

Nearest volume peer: Allergy to food (±0 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.

Lower-volume neighbourhood around Asystole

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

Vomiting · highest174348Allergy to food · near42Asystole · this reaction42Cholecystitis · near42Cutaneous emphysema · near42Digestive tract stasis · near42Urinary tract neoplas… · low…10
FDA AER report volume · neighbourhood around Asystole

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

Signature read: Asystole's 81.0% death-coded share is among the highest in the openFDA reaction corpus. Report volume is lower-third scale: 42 named reports in the openFDA extract. Death-coded share is upper-third: 34 of 42 reports (81.0% of named reports). Nearest volume peer: Allergy to food (±0 reports). Lead species Dog (29). Lead co-reported drug Butorphanol (11).

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 29
Cat 12
Human 1

Breeds Most Affected

Domestic Shorthair 9
Terrier - Bull - American Pit 3
Spaniel - King Charles Cavalier 3
Hound - Basset 3
American Pit Bull Terrier 2
Bulldog - French 2
Shepherd Dog - Australian 2
Chihuahua 2
Boxer (German Boxer) 2
Terrier - Yorkshire 1

Associated Drugs

Butorphanol 11
Isoflurane 10
Propofol 10
Dexmedetomidine Hydrochloride 7
Maropitant Citrate 7
Epinephrine 7
Dexmedetomidine 7
Gabapentin 6
Ketamine 6
Alfaxalone 6
Noinformationsupplied 6
Carprofen 5
Midazolam 5
Atipamezole Hydrochloride 4
Meloxicam 4
Pyrantel Pamoate;Sarolaner 4
Oclacitinib Maleate 3
Butorphanol Injectable 3
Hydromorphone 3
Intravenous Fluids 3

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 Asystole (#1824 of 2,481 by report volume); death-coded 81.0%. PlainBreed reaction plate · death-coded share stamp 81.0% · 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 →