Reaction profile
The FDA adverse-event record for muscle stiffness
578 FDA reports name muscle stiffness, a high-volume reaction in the CVM extract (VeDDRA 609). Plate stamps and neighbourhood peers follow.
- #589 of 2,481
- by report volume (all reactions)
- 578
- reports citing this reaction
- 17.1%
- 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. Muscle stiffness has 578 reports now versus 573 in that prior snapshot: 5 more (0.9%).
- Report change
- +5
- Death-coded reports
- +0
- Death-coded share
- −0.1 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 Muscle stiffness changesFDA AER · VeDDRA plate
Code 609 VOL-MID
VOL-MID · DEATH-ELEV · UPPER-Q · PHOTO-FINISH · SPECIES-DOG · DRUG-LEAD · DESK-WIDE · BOOK-FULL
- VOL-MID 578 reports
- DEATH-ELEV 17.1%
- UPPER-Q #589/2481
- PHOTO-FINISH Adrenal gland disorde…
- SPECIES-DOG Dog · 410
- DRUG-LEAD Milbemycin Oxime… · 58
- DESK-WIDE 20 breeds
- BOOK-FULL 8/8 fields
Nearest volume peer: Adrenal gland disorder NOS (±0 reports)
Upper-third report volume drives the scale stamps on this plate; death-coded share and co-report peers follow. Not a clinical diagnosis.
High-volume neighbourhood around Muscle stiffness
Upper-third volume poles plus nearest peers, not a full reaction corpus board reprint.
What the FDA AER plate says about Muscle stiffness
Signature read: 99 death-coded reports is a heavy tail count for Muscle stiffness in the CVM extract. Report volume is upper-third scale: 578 named reports in the openFDA extract. 99 of 578 reports were death-coded (17.1% of named reports, not a population mortality rate). Nearest volume peer: Adrenal gland disorder NOS (±0 reports). Lead species Dog (410). Lead co-reported drug Milbemycin Oxime + Spinosad (58).
Read these counts as reporting volume, not risk: per our methodology, Lead co-reported drug Milbemycin Oxime + Spinosad 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
Breeds Most Affected
Associated Drugs
Nationwide reactions with similar profiles
Two openFDA-derived peer sets for Muscle stiffness, 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 (578 here).
Similar death-coded share
Nearest other reactions by death-coded share (17.1% here), distinct from the volume row.
What to do with this reaction
- Compare Muscle stiffness'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 →