Reaction profile

The FDA adverse-event record for hydrocephalus

41 FDA reports name hydrocephalus, a lower-volume reaction in the CVM extract (VeDDRA 641). Plate stamps and neighbourhood peers follow.

#1837 of 2,481
by report volume (all reactions)
41
reports citing this reaction
70.7%
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. Hydrocephalus has 41 reports now versus 40 in that prior snapshot: 1 more (2.5%).

Report change
+1
Death-coded reports
+1
Death-coded share
+0.7 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 Hydrocephalus changes

FDA AER · VeDDRA plate

Code 641 VOL-TRACE

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

  • VOL-TRACE 41 reports
  • DEATH-HOT 70.7%
  • MID-PACK #1837/2481
  • PHOTO-FINISH Lack of efficacy (end…
  • SPECIES-DOG Dog · 40
  • DRUG-LEAD Milbemycin Oxime… · 7
  • DESK-WIDE 20 breeds
  • BOOK-FULL 8/8 fields

Nearest volume peer: Lack of efficacy (endoparasite) - strongylids (±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 Hydrocephalus

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

Vomiting · highest174348Hydrocephalus · this reaction41Lack of efficacy (end… · near41Loss of strength · near41Pemphigus · near41Sinusitis · near41Urinary tract neoplas… · low…10
FDA AER report volume · neighbourhood around Hydrocephalus

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

Signature read: Hydrocephalus's 70.7% death-coded share is among the highest in the openFDA reaction corpus. Report volume is lower-third scale: 41 named reports in the openFDA extract. Death-coded share is upper-third: 29 of 41 reports (70.7% of named reports). Nearest volume peer: Lack of efficacy (endoparasite) - strongylids (±0 reports). Lead species Dog (40). Lead co-reported drug Milbemycin Oxime + Spinosad (7).

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 40
Horse 1

Breeds Most Affected

Chihuahua 5
Boxer (German Boxer) 4
Retriever - Golden 3
Terrier - Bull - American Pit 3
Bulldog - French 3
Terrier - Yorkshire 2
Shepherd Dog - Australian 2
Shih Tzu 1
Spaniel - King Charles Cavalier 1
Pug 1

Associated Drugs

Milbemycin Oxime + Spinosad 7
Pyrantel Pamoate;Sarolaner 5
Afoxolaner 4
Maropitant Citrate 4
Sarolaner 3
Fluralaner 13.64% 12-Week Chew 3
Carprofen 2
Spinosad 2
Polysulfated Glycosaminoglycan 2
Fluralaner Chew Tablets 2
Acepromazine Maleate 2
Moxidectin 2
Diazepam 2
Prednisone 2
Bedinvetmab 2
Isoflurane 1
Milbemycin Oxime + Lufenuron 1
Gentamicin Sulfate + Betamethasone Valerate + Clotrimatzole 1
Selamectin 1
Ivermectin + Pyrantel As Pamoate Salt 1

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 Hydrocephalus (#1837 of 2,481 by report volume); death-coded 70.7%. PlainBreed reaction plate · death-coded share stamp 70.7% · 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 →