Reaction profile

The FDA adverse-event record for lack of efficacy (protozoa) - nos

670 FDA reports name lack of efficacy (protozoa) - nos, a high-volume reaction in the CVM extract (VeDDRA 2655). Plate stamps and neighbourhood peers follow.

#531 of 2,481
by report volume (all reactions)
670
reports citing this reaction
9.1%
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. Lack of efficacy (protozoa) - NOS has 670 reports now versus 668 in that prior snapshot: 2 more (0.3%).

Report change
+2
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 Lack of efficacy (protozoa) - NOS changes

FDA AER · VeDDRA plate

Code 2655 VOL-MID

VOL-MID · DEATH-PAR · UPPER-Q · PHOTO-FINISH · SPECIES-DOG · DRUG-LEAD · DESK-WIDE · BOOK-FULL

  • VOL-MID 670 reports
  • DEATH-PAR 9.1%
  • UPPER-Q #531/2481
  • PHOTO-FINISH Sedation prolonged
  • SPECIES-DOG Dog · 500
  • DRUG-LEAD Ivermectin + Pyra… · 163
  • DESK-WIDE 20 breeds
  • BOOK-FULL 8/8 fields

Nearest volume peer: Sedation prolonged (±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 Lack of efficacy - NOS

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

Vomiting · highest174348Involuntary defecation · near673Respiratory arrest · near673Lack of efficacy (pro… · thi…670Sedation prolonged · near670Urine leakage · near668Urinary tract neoplas… · low…10
FDA AER report volume · neighbourhood around Lack of efficacy (protozoa) - NOS

What the FDA AER plate says about Lack of efficacy (protozoa) - NOS

Signature read: 670 reports place Lack of efficacy (protozoa) - NOS in the upper third of FDA AER volume (#531 of 2,481). Report volume is upper-third scale: 670 named reports in the openFDA extract. 61 of 670 reports were death-coded (9.1% of named reports, not a population mortality rate). Nearest volume peer: Sedation prolonged (±0 reports). Lead species Dog (500). Lead co-reported drug Ivermectin + Pyrantel As Pamoate Salt (163).

Read these counts as reporting volume, not risk: per our methodology, Lead co-reported drug Ivermectin + Pyrantel As Pamoate Salt 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 500
Cat 98
Horse 59
Cattle 10
Guinea Pig 1
Chicken 1
Macaw 1

Breeds Most Affected

Retriever - Labrador 89
Domestic Shorthair 70
Crossbred Canine/dog 47
Retriever - Golden 39
Shepherd Dog - German 35
Shepherd Dog - Australian 18
Beagle 17
Quarter Horse 16
Collie - Border 12
Terrier - Yorkshire 11

Associated Drugs

Ivermectin + Pyrantel As Pamoate Salt 163
Milbemycin Oxime, Lufenuron 48
Fenbendazol Granules 39
Fluralaner Spot-On Solution 39
Milbemycin Oxime + Spinosad 37
Fluralaner/Moxidectin Spot-On 36
Diclazuril Oral Pellets 29
Milbemycin Oxime 22
Ponazuril 20
Lufenuron + Milbemycin Oxime 19
Milbemycin 18
Selamectin 17
Pyrantel Pamoate;Sarolaner 16
Ivermectin/Pyrantel Pamoate Chewable 272Mcg/652Mg 15
Ivermectin/Pyrantel Pamoate Chewable 68Mcg/163Mg 14
Milbemcyin Oxime, Lufenuron, Praziquantel 14
Ivermectin, Pyrantel 13
Ivermectin/Pyrantel Pamoate Chewable 136Mcg/326Mg 13
Milbemycin, Lufenuron 10
Ivermectin + Pyrantel 8

Nationwide reactions with similar profiles

Two openFDA-derived peer sets for Lack of efficacy (protozoa) - NOS, 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 (670 here).

Similar death-coded share

Nearest other reactions by death-coded share (9.1% here), distinct from the volume row.

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 Lack of efficacy (protozoa) - NOS (#531 of 2,481 by report volume); death-coded 9.1%. PlainBreed reaction plate · report volume stamp 670 · 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 →