Reaction profile

The FDA adverse-event record for encephalitis

140 FDA adverse-event reports reference encephalitis (VeDDRA 633). See the species, breeds, and drugs most associated with it below.

140
reports citing this reaction
51.4%
death-coded share
Dog
most-affected species
Milbemycin Oxime + Spinosad
most-associated drug
Verify with FDA CVM →
140
Total Reports
72
Deaths
51.4%
Death Rate

Species Most Affected

Dog 112
Cat 13
Cattle 8
Human 1
Rabbit 1
Other Birds 1
Ferret 1
Goat 1
Horse 1
Pig 1

Breeds Most Affected

Retriever - Golden 13
Domestic Shorthair 11
Terrier - Yorkshire 8
Retriever - Labrador 7
Crossbred Canine/dog 6
Chihuahua 5
Maltese 5
Shih Tzu 4
Terrier (unspecified) 4
Unknown 3

Associated Drugs

Milbemycin Oxime + Spinosad 18
Moxidectin 12
Fluralaner Chew Tablets 11
Maropitant Citrate 9
Spinosad 8
Afoxolaner 8
Carprofen 8
Pyrantel Pamoate;Sarolaner 8
Enrofloxacin 7
Prednisone 6
Meloxicam 6
Sarolaner 6
Bedinvetmab 6
Cefovecin 5
Doxycycline 5
Clindamycin 5
Oclacitinib Maleate 5
Fluralaner 13.64% 12-Week Chew 5
Phenobarbital 4
Diazepam 4

Encephalitis Reaction Insights

140 reports name Encephalitis; 72 recorded a death outcome (51.4% of reported events, not a population-level mortality rate). VeDDRA code: 633.

By species: Dog (112 reports), Cat (13 reports), Cattle (8 reports). By breed: Retriever - Golden (13), Domestic Shorthair (11), Terrier - Yorkshire (8).

Most co-reported drugs: Milbemycin Oxime + Spinosad (18 reports), Moxidectin (12 reports), Fluralaner Chew Tablets (11 reports), Maropitant Citrate (9 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.