Reaction profile

The FDA adverse-event record for heart block nos

118 FDA adverse-event reports reference heart block nos (VeDDRA 191). See the species, breeds, and drugs most associated with it below.

118
reports citing this reaction
11.0%
death-coded share
Dog
most-affected species
Dexmedetomidine Hydrochloride
most-associated drug
Verify with FDA CVM →
118
Total Reports
13
Deaths
11.0%
Death Rate

Species Most Affected

Dog 113
Cat 4
Human 1

Breeds Most Affected

Dog (unknown) 20
Retriever - Labrador 8
Unknown 7
Retriever - Golden 5
Shepherd Dog - Australian 5
Shepherd Dog - German 4
Boxer (German Boxer) 3
Chihuahua 3
Terrier - Bull - American Pit 3
Pointing Dog - German Short-haired 3

Associated Drugs

Dexmedetomidine Hydrochloride 42
Propofol 33
Isoflurane 25
Butorphanol 19
Milbemycin Oxime + Spinosad 15
Maropitant Citrate 13
Sevoflurane 9
Dexmedetomidine 8
Butorphanol Tartrate 8
Buprenorphine 6
Hydromorphone Hcl Injectable 6
Carprofen 5
Atropine 5
Atipamezole 5
Meloxicam 4
Atipamezole Hydrochloride 4
Acepromazine Maleate 4
Acepromazine 4
Midazolam 4
Anesthetic 4

Heart block NOS Reaction Insights

118 reports name Heart block NOS; 13 recorded a death outcome (11.0% of reported events, not a population-level mortality rate). VeDDRA code: 191.

By species: Dog (113 reports), Cat (4 reports), Human (1 reports). By breed: Dog (unknown) (20), Retriever - Labrador (8), Unknown (7).

Most co-reported drugs: Dexmedetomidine Hydrochloride (42 reports), Propofol (33 reports), Isoflurane (25 reports), Butorphanol (19 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.