Reaction profile

The FDA adverse-event record for syncope

332 FDA adverse-event reports reference syncope (VeDDRA 226). See the species, breeds, and drugs most associated with it below.

332
reports citing this reaction
25.0%
death-coded share
Dog
most-affected species
Pimobendan
most-associated drug
Verify with FDA CVM →
332
Total Reports
83
Deaths
25.0%
Death Rate

Species Most Affected

Dog 303
Cat 16
Human 8
Horse 3
Goat 1
Other 1

Breeds Most Affected

Crossbred Canine/dog 25
Boxer (German Boxer) 23
Chihuahua 22
Retriever - Labrador 19
Shih Tzu 16
Dog (unknown) 12
Maltese 11
Unknown 10
Spitz - German Pomeranian 10
Spaniel - King Charles Cavalier 9

Associated Drugs

Pimobendan 77
Bedinvetmab 32
Milbemycin Oxime + Spinosad 30
Furosemide 22
Trilostane 22
Pyrantel Pamoate;Sarolaner 22
Moxidectin 20
Gabapentin 17
Enalapril 15
Spinosad 14
Melarsomine Dihydrochloride 13
Maropitant Citrate 12
Afoxolaner 9
Carprofen 8
Oclacitinib Maleate 8
Ivermectin + Pyrantel As Pamoate Salt 8
Cyclosporine 7
Enalapril Maleate 7
Fluralaner Chew Tablets 7
Sarolaner 7

Syncope Reaction Insights

332 reports name Syncope; 83 recorded a death outcome (25.0% of reported events, not a population-level mortality rate). VeDDRA code: 226.

By species: Dog (303 reports), Cat (16 reports), Human (8 reports). By breed: Crossbred Canine/dog (25), Boxer (German Boxer) (23), Chihuahua (22).

Most co-reported drugs: Pimobendan (77 reports), Bedinvetmab (32 reports), Milbemycin Oxime + Spinosad (30 reports), Furosemide (22 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.