Reaction profile

The FDA adverse-event record for hard, clumping

2,913 FDA adverse-event reports reference hard, clumping (VeDDRA 99953). See the species, breeds, and drugs most associated with it below.

2,913
reports citing this reaction
0.1%
death-coded share
Unknown
most-affected species
Ivermectin + Pyrantel As Pamoate Salt
most-associated drug
Verify with FDA CVM →
2,913
Total Reports
2
Deaths
0.1%
Death Rate

Species Most Affected

Unknown 2,801
Dog 101
Cat 5
White tailed deer 2
Chicken 2
Cattle 2

Breeds Most Affected

Unknown 2,803
Crossbred Canine/dog 14
Dog (unknown) 7
Retriever - Labrador 5
Shepherd Dog - Australian 4
Dachshund (unspecified) 4
Retriever - Golden 4
Poodle - Standard 4
Chihuahua 4
Shih Tzu 3

Associated Drugs

Ivermectin + Pyrantel As Pamoate Salt 1,462
Afoxolaner 619
Moxidectin 159
Pyrantel Pamoate;Sarolaner 114
Fluralaner 13.64% 12-Week Chew 83
Cefovecin 44
Milbemycin/Lufenuron/Pzq Chew 39
Fluralaner Chew Tablets 36
Ivermectin 29
Oclacitinib Maleate 19
Decoquinate 18
Lufenuron + Milbemycin Oxime + Praziquantel 18
Amoxicillin Trihydrate;Clavulanate Potassium ( K-Clavulanate) 15
Insulin Injectable Vial 14
Carprofen 13
Afoxolaner 136 Mg Chewable Tablets 13
Ceftiofur Sodium 13
Afoxolaner 68 Mg Chewable Tablets 12
Ivermectin/Pyrantel Pamoate Chewable 68Mcg/163Mg 11
Ivermectin + Pyrantel 10

Hard, clumping Reaction Insights

2,913 reports name Hard, clumping; 2 recorded a death outcome (0.1% of reported events, not a population-level mortality rate). VeDDRA code: 99953.

By species: Unknown (2,801 reports), Dog (101 reports), Cat (5 reports). By breed: Unknown (2,803), Crossbred Canine/dog (14), Dog (unknown) (7).

Most co-reported drugs: Ivermectin + Pyrantel As Pamoate Salt (1,462 reports), Afoxolaner (619 reports), Moxidectin (159 reports), Pyrantel Pamoate;Sarolaner (114 reports).

Read these counts as reporting volume, not risk: per our methodology, co-reporting reflects temporal association captured in voluntary submissions, not proof that a drug caused this reaction. A widely-prescribed drug will rack up more raw co-reports at an identical true rate than a rarely-used one, so compare within similar-exposure products.

Source: FDA Center for Veterinary Medicine openFDA Animal & Veterinary Adverse Events (CVM AER) · 2025

Every figure on PlainBreed is rendered directly from FDA openFDA adverse event data, no number is typed in by an editor. This page draws directly on FDA openFDA data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.