Reaction profile

The FDA adverse-event record for high free thyroxine (ft4)

19 FDA reports name high free thyroxine (ft4), a lower-volume reaction in the CVM extract (VeDDRA 2704). Plate stamps and neighbourhood peers follow.

#2182 of 2,481
by report volume (all reactions)
19
reports citing this reaction
15.8%
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. High free thyroxine (FT4) has 19 reports now versus 18 in that prior snapshot: 1 more (5.6%).

Report change
+1
Death-coded reports
+0
Death-coded share
−0.9 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 High free thyroxine (FT4) changes

FDA AER · VeDDRA plate

Code 2704 VOL-TRACE

VOL-TRACE · DEATH-ELEV · LOWER-Q · PHOTO-FINISH · SPECIES-DOG · DRUG-LEAD · DESK-WIDE · BOOK-FULL

  • VOL-TRACE 19 reports
  • DEATH-ELEV 15.8%
  • LOWER-Q #2182/2481
  • PHOTO-FINISH Adaptor, damaged
  • SPECIES-DOG Dog · 11
  • DRUG-LEAD Levothyroxine Sod… · 3
  • DESK-WIDE 10 breeds
  • BOOK-FULL 8/8 fields

Nearest volume peer: Adaptor, damaged (±0 reports)

Instrument codes from this reaction’s FDA CVM adverse-event extract: volume band, death-coded share, corpus rank, photo-finish peer, lead species, lead drug, breed desk, and book completeness. Not a clinical diagnosis.

Lower-volume neighbourhood around High free thyroxine

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

Vomiting · highest174348Adaptor, damaged · near19Amaurosis (see also P… · near19Anhidrosis · near19Cholelithiasis · near19High free thyroxine (… · thi…19Urinary tract neoplas… · low…10
FDA AER report volume · neighbourhood around High free thyroxine (FT4)

What the FDA AER plate says about High free thyroxine (FT4)

Signature read: 19 reports place High free thyroxine (FT4) in the lower third of FDA AER volume (#2182 of 2,481). Report volume is lower-third scale: 19 named reports in the openFDA extract. 3 of 19 reports were death-coded (15.8% of named reports, not a population mortality rate). Nearest volume peer: Adaptor, damaged (±0 reports). Lead species Dog (11). Lead co-reported drug Levothyroxine Sodium (3).

Read these counts as reporting volume, not risk: per our methodology, Lead co-reported drug Levothyroxine Sodium 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 11
Cat 8

Breeds Most Affected

Domestic Shorthair 8
Dachshund - Standard Long-haired 2
Pug 2
Sheepdog - Shetland 1
Pinscher - Miniature 1
Coonhound - Black and Tan 1
Retriever - Labrador 1
Dalmatian 1
Crossbred Canine/dog 1
Bichon Frise 1

Associated Drugs

Levothyroxine Sodium 3
Maropitant Citrate 3
Trilostane 3
Neomycin/Polymyxin B Sulfates/Dexamethasone Ophthalmic Suspension 3
Doxycycline 3
Insulin 3
Fluralaner Spot-On Solution 2
Insulin Injectable Vial 2
Cefovecin 2
Frunevetmab 2
Enrofloxacin 2
Methimazole 2
Bedinvetmab 2
Penobarbital 2
Butorphanol 2
Buprenorphine 2
Ursodiol 2
Ampicillin Sodium/Sulbactam Sodium 2
S-Adenosylmethionine + Silybin 2
Gabapentin 2

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 High free thyroxine (FT4) (#2182 of 2,481 by report volume); death-coded 15.8%. PlainBreed reaction plate · report volume stamp 19 · 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 →