Drug profile

The FDA adverse-event record for Dextromethorphan + Guaifenisen

19 FDA reports name Dextromethorphan + Guaifenisen, a lower-volume drug in the CVM extract. Species, reactions, and outcomes follow.

#1834 of 2,679
by report volume (all drugs)
19
adverse-event reports
10.5%
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, Dextromethorphan + Guaifenisen ranks #1827 of 2679 by total reports (19). 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)
#1827
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. Dextromethorphan + Guaifenisen has 19 reports now versus 18 in that prior snapshot: 1 more (5.6%).

Report change
+1
Death-coded reports
+0
Death-coded share
−0.6 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 Dextromethorphan + Guaifenisen changes

Signature read: 19 reports place Dextromethorphan + Guaifenisen in the lower third of FDA AER volume (#1834 of 2,679).

Important: Adverse event reports do not establish that a drug caused or contributed to the event. Consult your veterinarian before making treatment decisions.
19
Total Reports
2
Deaths Reported
10.5%
Death-coded share of reports

Active Ingredients

Dextromethorphan + Guaifenisen

Administration Routes

UnknownOral

Species Affected

Dog 19

Most Affected Breeds

Retriever - Labrador 7
Dachshund (unspecified) 2
Setter - English 1
Chihuahua 1
Sheepdog - Old English 1
Pit Bull 1
Pekingese 1
Terrier (unspecified) 1
Great Pyrenees 1
Spitz - German Pomeranian 1

Most Reported Reactions

Emesis 6
Breathing difficulty 5
Elevated alanine aminotransferase (ALT) 4
Decreased haematocrit 4
Cough, hacking 4
Nasal discharge 4
Wheezing 4
Abnormal radiograph finding 4
Sneezing 4
Vomiting bile 4
Cough, productive 4
Tiredness 4

Outcome Breakdown

Recovered/Normal
9 (47.4%)
Ongoing
5 (26.3%)
Outcome Unknown
3 (15.8%)
Died
2 (10.5%)

Dextromethorphan + Guaifenisen: lower report volume in the FDA AER row

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 Dextromethorphan + Guaifenisen (#1834 of 2,679 by report volume); death-coded 10.5%. PlainBreed drug row · report volume stamp 19 · 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 →