Reaction profile

The FDA adverse-event record for constipation

1,965 FDA adverse-event reports reference constipation (VeDDRA 267). See the species, breeds, and drugs most associated with it below.

1,965
reports citing this reaction
15.3%
death-coded share
Dog
most-affected species
Milbemycin Oxime + Spinosad
most-associated drug
Verify with FDA CVM →
1,965
Total Reports
300
Deaths
15.3%
Death Rate

Species Most Affected

Dog 1,205
Cat 723
Human 13
Horse 13
Ferret 3
Cattle 3
Pig 3
Guinea Pig 1
Other Rodents 1

Breeds Most Affected

Domestic Shorthair 397
Retriever - Labrador 100
Crossbred Canine/dog 88
Shih Tzu 65
Chihuahua 56
Dog (unknown) 54
Terrier - Yorkshire 54
Cat (unknown) 52
Domestic Longhair 52
Domestic Mediumhair 45

Associated Drugs

Milbemycin Oxime + Spinosad 162
Maropitant Citrate 160
Buprenorphine 149
Carprofen 122
Cefovecin 95
Robenacoxib 78
Frunevetmab 76
Spinosad 73
Gabapentin 72
Meloxicam 67
Selamectin 66
Afoxolaner 62
Fluralaner Chew Tablets 55
Ivermectin + Pyrantel As Pamoate Salt 54
Oclacitinib Maleate 46
Prednisone 43
Famotidine 41
Trilostane 41
Pyrantel Pamoate;Sarolaner 39
Grapiprant 38

Constipation Reaction Insights

1,965 reports name Constipation; 300 recorded a death outcome (15.3% of reported events, not a population-level mortality rate). VeDDRA code: 267.

By species: Dog (1,205 reports), Cat (723 reports), Human (13 reports). By breed: Domestic Shorthair (397), Retriever - Labrador (100), Crossbred Canine/dog (88).

Most co-reported drugs: Milbemycin Oxime + Spinosad (162 reports), Maropitant Citrate (160 reports), Buprenorphine (149 reports), Carprofen (122 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.