Reaction profile

The FDA adverse-event record for ineffective, heartworm adults

2,694 FDA reports name ineffective, heartworm adults, a high-volume reaction in the CVM extract (VeDDRA 99114). Plate stamps and neighbourhood peers follow.

#175 of 2,481
by report volume (all reactions)
2,694
reports citing this reaction
0.4%
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. INEFFECTIVE, HEARTWORM ADULTS has 2,694 reports now versus 2,694 in that prior snapshot: 0 the same number of (0.0%).

Report change
+0
Death-coded reports
+0
Death-coded share
+0.0 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 INEFFECTIVE, HEARTWORM ADULTS changes

FDA AER · VeDDRA plate

Code 99114 VOL-MID

VOL-MID · DEATH-RARE · TOP-DECILE · PHOTO-FINISH · SPECIES-DOG · DRUG-LEAD · DESK-WIDE · BOOK-FULL

  • VOL-MID 2,694 reports
  • DEATH-RARE 0.4%
  • TOP-DECILE #175/2481
  • PHOTO-FINISH Monocytosis
  • SPECIES-DOG Dog · 2,694
  • DRUG-LEAD Melarsomine Dihyd… · 1,260
  • DESK-WIDE 20 breeds
  • BOOK-FULL 8/8 fields

Nearest volume peer: Monocytosis (±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 INEFFECTIVE, HEARTWORM ADULTS

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

Vomiting · highest174348Elevated serum alkali… · near2701INEFFECTIVE, HEARTWOR… · thi…2694Monocytosis · near2694Abnormal posture NOS · near2693Eye disorder NOS (for… · near2682Urinary tract neoplas… · low…10
FDA AER report volume · neighbourhood around INEFFECTIVE, HEARTWORM ADULTS

INEFFECTIVE, HEARTWORM ADULTS: low death-coded share in the FDA AER plate

Signature read: 2,694 reports place INEFFECTIVE, HEARTWORM ADULTS in the upper third of FDA AER volume (#175 of 2,481). Report volume is upper-third scale: 2,694 named reports in the openFDA extract. Death-coded share is lower-third: 11 of 2,694 reports (0.4% of named reports). Nearest volume peer: Monocytosis (±0 reports). Lead species Dog (2,694). Lead co-reported drug Melarsomine Dihydrochloride Injection (1,260).

Read these counts as reporting volume, not risk: per our methodology, Lead co-reported drug Melarsomine Dihydrochloride Injection 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 2,694

Breeds Most Affected

Crossbred Canine/dog 438
Retriever - Labrador 310
Beagle 197
Chihuahua 156
Dog (unknown) 137
Shepherd Dog - German 113
Pit Bull 101
Dog (other) 88
Boxer (German Boxer) 80
Rottweiler 53

Associated Drugs

Melarsomine Dihydrochloride Injection 1,260
Melarsomine Dihydrochloride 1,087
Ivermectin + Pyrantel As Pamoate Salt 727
Melarsomine 208
Ivermectin + Pyrantel 181
Melarsomine Dihydrocloride Injectable 25Mg/Ml 127
Doxycycline 113
Ivermectin 70
Ivermectin/Pyrantel Pamoate Chewable 272Mcg/652Mg 48
Prednisone 41
Ivermectin/Pyrantel Pamoate Chewable 68Mcg/163Mg 37
Ivermectin/Pyrantel Chew. Dog 272Mcg/227Mg 28
Ivermectin/Pyrantel Pamoate Chewable 136Mcg/326Mg 26
Ivermectin & Pyrantel 24
Milbemycin Oxime 24
Ivermectin/Pyrantel Chew. Dog 68Mcg/57Mg 15
Prednisolone 14
Moxidectin 13
Ivermectin/Pyrantel 10
Ivermectin 1% Injection 8

Nationwide reactions with similar profiles

Two openFDA-derived peer sets for INEFFECTIVE, HEARTWORM ADULTS, both floored at ≥50 reports so the neighborhoods stay in the advertised mass (the volume chart above is the unfloored photo-finish strip).

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 INEFFECTIVE, HEARTWORM ADULTS (#175 of 2,481 by report volume); death-coded 0.4%. PlainBreed reaction plate · report volume stamp 2,694 · 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 →