Reaction profile
The FDA adverse-event record for monocytosis
2,694 FDA reports name monocytosis, a high-volume reaction in the CVM extract (VeDDRA 2420). Plate stamps and neighbourhood peers follow.
- #176 of 2,481
- by report volume (all reactions)
- 2,694
- reports citing this reaction
- 28.4%
- 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. Monocytosis has 2,694 reports now versus 2,577 in that prior snapshot: 117 more (4.5%).
- Report change
- +117
- Death-coded reports
- +23
- Death-coded share
- −0.4 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 Monocytosis changesFDA AER · VeDDRA plate
Code 2420 VOL-MID
VOL-MID · DEATH-HOT · TOP-DECILE · PHOTO-FINISH · SPECIES-DOG · DRUG-LEAD · DESK-WIDE · BOOK-FULL
- VOL-MID 2,694 reports
- DEATH-HOT 28.4%
- TOP-DECILE #176/2481
- PHOTO-FINISH INEFFECTIVE, HEARTWOR…
- SPECIES-DOG Dog · 2,219
- DRUG-LEAD Maropitant Citrate · 346
- DESK-WIDE 20 breeds
- BOOK-FULL 8/8 fields
Nearest volume peer: INEFFECTIVE, HEARTWORM ADULTS (±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.
High-volume neighbourhood around Monocytosis
Upper-third volume poles plus nearest peers, not a full reaction corpus board reprint.
Monocytosis: high death-coded share in the FDA AER plate
Signature read: 766 death-coded reports is a heavy tail count for Monocytosis in the CVM extract. Report volume is upper-third scale: 2,694 named reports in the openFDA extract. Death-coded share is upper-third: 766 of 2,694 reports (28.4% of named reports). Nearest volume peer: INEFFECTIVE, HEARTWORM ADULTS (±0 reports). Lead species Dog (2,219). Lead co-reported drug Maropitant Citrate (346).
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
Breeds Most Affected
Associated Drugs
Nationwide reactions with similar profiles
Two openFDA-derived peer sets for Monocytosis, 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 (2,694 here).
Similar death-coded share
Nearest other reactions by death-coded share (28.4% here), distinct from the volume row.
What to do with this reaction
- Compare Monocytosis's report profile against similar reactions nationwide. See similar reactions
- Read how death-coded share differs from a mortality rate before drawing conclusions. Understanding adverse events
- Browse the full reaction directory to compare report counts across reaction types. All reactions
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
Informational only. FDA adverse-event reports are voluntary and do not prove causation; consult a veterinarian before acting on them. Verify with FDA CVM →