Drug profile

The FDA adverse-event record for Doxycyline

31 adverse-event reports submitted to the FDA Center for Veterinary Medicine reference Doxycyline. Species, reactions, and outcomes follow.

#1422 of 2,679
by report volume (all drugs)
31
adverse-event reports
16.1%
death-coded share
Dog
most-reported species
Verify with FDA CVM →

Corpus placement

According to the FDA Center for Veterinary Medicine openFDA adverse-event extract, Doxycyline ranks #1412 of 2679 by total reports (31). Death-coded-share rank requires at least 50 reports. National dual: Milbemycin Oxime + Spinosad is #1 of 2679 drugs by total adverse-event reports (149,624) at death-coded-share rank 965 of 1130 drugs with at least 50 reports (2.3%); separately, Atlantic Salmon Transgenic Whole (Opafp-Ghc2 Rdna Construct Inserted Into The A-Locus In The Eo-1A Lineage) is #1 highest death-coded share at 97.8% (report rank #821).

149,624
Milbemycin Oxime + Spinosad reports (#1)
97.8%
Atlantic Salmon Transgenic Whole (Opafp-Ghc2 Rdna Construct Inserted Into The A-Locus In The Eo-1A Lineage) death share (#1)
#1412
This drug, reports of 2679

Report volume reflects how common a breed or drug is and how often owners and vets file — not actual risk. Death-coded share ranks are limited to entries with enough reports to be meaningful. The two maps do not agree at #1.

Release-over-release change

What changed in the latest FDA data snapshot

PlainBreed reconstructed the prior snapshot from dated openFDA partitions through 2025 Q4, then compared it with the 2026-07-27 openFDA export. Doxycyline has 31 reports now versus 31 in that prior snapshot: 0 the same number of (0.0%).

Report change
+0
Death-coded reports
+0
Death-coded share
+0.0 pts

This compares reported-event counts in two source snapshots. It does not establish a change in real-world risk, product safety, or disease incidence.

Subscribe to Doxycyline changes

Signature read: death-coded share at 16.1% is the most distinctive stamp on Doxycyline's FDA AER row.

Important: Adverse event reports do not establish that a drug caused or contributed to the event. Consult your veterinarian before making treatment decisions.
31
Total Reports
5
Deaths Reported
16.1%
Death-coded share of reports

Active Ingredients

Doxycyline

Administration Routes

OralUnknown

Species Affected

Dog 29
Cat 1
Horse 1

Most Affected Breeds

Retriever - Labrador 5
Crossbred Canine/dog 2
Cattle Dog - Australian (blue heeler, red heeler, Queensland cattledog) 2
Poodle - Standard 2
Terrier - Bull - Staffordshire 2
Pointing Dog - Hungarian Short-haired (Vizsla) 2
Collie - Border 1
Shepherd Dog - Australian 1
Domestic Longhair 1
Deutsche Dogge, Great Dane 1

Most Reported Reactions

Vomiting 6
Lack of efficacy (endoparasite) - heartworm 6
Ataxia 5
Death by euthanasia 4
Diarrhoea 4
Elevated alanine aminotransferase (ALT) 4
Not eating 4
Decreased appetite 3
Abnormal pupil light reflex 3
Weight loss 3
Lack of efficacy (endoparasite) - hookworm 3
Lack of efficacy (bacteria) - Borrelia 3

Outcome Breakdown

Outcome Unknown
15 (48.4%)
Recovered/Normal
6 (19.4%)
Ongoing
5 (16.1%)
Euthanized
3 (9.7%)
Died
2 (6.5%)

Doxycyline Adverse Event Insights

Read these counts as reporting volume, not risk: per our methodology, a widely-prescribed drug will rack up more raw FDA reports in a given year than a rarely-used one at an identical true rate, so we recommend comparing within similar-exposure products rather than across the full 2025 catalog.

What to do with this drug

A report does not prove a drug caused the reaction; consult a veterinarian before acting on this data.

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

openFDA Animal & Veterinary Adverse Events (FDA CVM) for Doxycyline (#1422 of 2,679 by report volume); death-coded 16.1%. PlainBreed drug row · death-coded share stamp 16.1% · vintage 2025.

Informational only. FDA adverse-event reports are voluntary and do not prove causation; consult a veterinarian before acting on them. Verify with FDA CVM →