Drug profile

The FDA adverse-event record for Melarsomine Dihydrochloride Injection

5,095 FDA reports name Melarsomine Dihydrochloride Injection, a high-volume drug in the CVM extract. Species, reactions, and outcomes follow.

#46 of 2,679
by report volume (all drugs)
5,095
adverse-event reports
3.9%
death-coded share
Dog
most-reported species

Corpus placement

According to the FDA Center for Veterinary Medicine openFDA adverse-event extract, Melarsomine Dihydrochloride Injection ranks #46 of 2679 by total reports (5,095) and #857 of 1130 by death-coded share (3.9%). 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)
#46
This drug, reports of 2679
#857
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. Melarsomine Dihydrochloride Injection has 5,095 reports now versus 5,095 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 Melarsomine Dihydrochloride Injection changes

Signature read: 5,095 reports place Melarsomine Dihydrochloride Injection in the upper third of FDA AER volume (#46 of 2,679).

Important: Adverse event reports do not establish that a drug caused or contributed to the event. Consult your veterinarian before making treatment decisions.
5,095
Total Reports
198
Deaths Reported
3.9%
Death-coded share of reports

Active Ingredients

Melarsomine Dihydrochloride Injection

Administration Routes

IntramuscularUnknownSubcutaneousOralOphthalmicParenteralIntravenous

Species Affected

Dog 4,570
Unknown 507
Human 18

Most Affected Breeds

Crossbred Canine/dog 681
Retriever - Labrador 607
Unknown 541
Dog (unknown) 304
Pit Bull 249
Shepherd Dog - German 244
Dog (other) 240
Beagle 207
Chihuahua 174
Boxer (German Boxer) 170

Most Reported Reactions

INEFFECTIVE, HEARTWORM ADULTS 1,260
INEFFECTIVE, HEARTWORM LARVAE 627
Vomiting 595
Injection site swelling 487
Cardiac disorder NOS 458
Lethargy (see also Central nervous system depression in 'Neurological') 442
Pain NOS 330
Vials, Damaged 325
Injection site pain 320
Panting 312
Other abnormal test result NOS 299
Injection site lump 297

Outcome Breakdown

Outcome Unknown
2,939 (64.0%)
Recovered/Normal
613 (13.3%)
Ongoing
518 (11.3%)
Recovered with Sequela
326 (7.1%)
Died
138 (3.0%)
Euthanized
60 (1.3%)

Melarsomine Dihydrochloride Injection: low death-coded share in the FDA AER row

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.

High-volume nationwide drug peers

Two openFDA-derived peer sets for Melarsomine Dihydrochloride Injection, both floored at ≥50 reports so the neighborhoods stay in the advertised mass.

What to do with this drug

  • Compare Melarsomine Dihydrochloride Injection'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

openFDA Animal & Veterinary Adverse Events (FDA CVM) for Melarsomine Dihydrochloride Injection (#46 of 2,679 by report volume); death-coded 3.9%. PlainBreed drug row · report volume stamp 5,095 · 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 →