Drug profile
The FDA adverse-event record for Heartworm Preventative
71 adverse-event reports submitted to the FDA Center for Veterinary Medicine reference Heartworm Preventative. Species, reactions, and outcomes follow.
- #929 of 2,679
- by report volume (all drugs)
- 71
- adverse-event reports
- 7.0%
- death-coded share
- Dog
- most-reported species
Corpus placement
According to the FDA Center for Veterinary Medicine openFDA adverse-event extract, Heartworm Preventative ranks #928 of 2679 by total reports (71) and #696 of 1130 by death-coded share (7.0%). National dual: Milbemycin Oxime + Spinosad is #1 of 2679 drugs by total adverse-event reports (149,624) at death-coded-share rank 965 of 1130 drugs with at least 50 reports (2.3%); separately, Atlantic Salmon Transgenic Whole (Opafp-Ghc2 Rdna Construct Inserted Into The A-Locus In The Eo-1A Lineage) is #1 highest death-coded share at 97.8% (report rank #821).
- 149,624
- Milbemycin Oxime + Spinosad reports (#1)
- 97.8%
- Atlantic Salmon Transgenic Whole (Opafp-Ghc2 Rdna Construct Inserted Into The A-Locus In The Eo-1A Lineage) death share (#1)
- #928
- This drug, reports of 2679
- #696
- This drug, death share of 1130
Report volume reflects how common a breed or drug is and how often owners and vets file — not actual risk. Death-coded share ranks are limited to entries with enough reports to be meaningful. The two maps do not agree at #1.
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. Heartworm Preventative has 71 reports now versus 69 in that prior snapshot: 2 more (2.9%).
- Report change
- +2
- Death-coded reports
- +0
- Death-coded share
- −0.2 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 Heartworm Preventative changesSignature read: report volume at 71 is the most distinctive stamp on Heartworm Preventative's FDA AER row.
Active Ingredients
Administration Routes
Species Affected
Most Affected Breeds
Most Reported Reactions
Outcome Breakdown
Heartworm Preventative Adverse Event Insights
Read these counts as reporting volume, not risk: per our methodology, a widely-prescribed drug will rack up more raw FDA reports in a given year than a rarely-used one at an identical true rate, so we recommend comparing within similar-exposure products rather than across the full 2025 catalog.
Nationwide drugs with similar profiles
Two openFDA-derived peer sets for Heartworm Preventative, both floored at ≥50 reports so the neighborhoods stay in the advertised mass.
Similar report volume
Nearest other drugs by FDA report count (71 here).
Similar death-coded share
Nearest other drugs by death-coded share (7.0% here), distinct from the volume row.
What to do with this drug
- Compare Heartworm Preventative's report volume and death-coded share against similar drugs nationwide. See similar drugs
- Read how death-coded share differs from a mortality rate before drawing conclusions. Understanding adverse events
- Browse the full drug directory to compare report counts across products. All drugs
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 →