Drug profile

The FDA adverse-event record for Penicillin G

43 adverse-event reports submitted to the FDA Center for Veterinary Medicine reference Penicillin G. See the species affected, top reactions, and outcomes below.

43
adverse-event reports
27.9%
death-coded share
Dog
most-reported species
10
Vomiting - top reaction
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Important: Adverse event reports do not establish that a drug caused or contributed to the event. Consult your veterinarian before making treatment decisions.
43
Total Reports
12
Deaths Reported
27.9%
Death Rate

Active Ingredients

Penicillin G

Administration Routes

UnknownSubcutaneousIntravenousIntramuscularIntramammaryOral

Species Affected

Dog 22
Unknown 7
Cat 6
Cattle 3
Horse 2
Pig 1
Alpaca 1
Tiger 1

Most Affected Breeds

Unknown 11
Domestic Shorthair 5
Retriever - Labrador 3
Pug 3
Dog (unknown) 2
Charolais 1
Dachshund (unspecified) 1
Domestic Longhair 1
Sheepdog - Shetland 1
Bichon Frise 1

Most Reported Reactions

Vomiting 10
Death by euthanasia 7
Elevated alanine aminotransferase (ALT) 6
Seizure NOS 6
Other abnormal test result NOS 6
Death 5
Lethargy (see also Central nervous system depression in 'Neurological') 5
Potency, Low 5
Anorexia 4
Elevated serum alkaline phosphatase (SAP) 4
Weight loss 4
Dehydration 4

Outcome Breakdown

Recovered/Normal
12 (30.8%)
Ongoing
8 (20.5%)
Euthanized
7 (17.9%)
Died
6 (15.4%)
Outcome Unknown
6 (15.4%)

Penicillin G Adverse Event Insights

43 reports name Penicillin G; 12 recorded a death outcome (27.9% of reported events, not a population-level mortality rate). Active ingredient: Penicillin G. Administration routes: Unknown, Subcutaneous, Intravenous, Intramuscular.

By species: Dog (22 reports), Unknown (7 reports), Cat (6 reports). By breed: Unknown (11), Domestic Shorthair (5), Retriever - Labrador (3).

Leading clinical signs: Vomiting (10), Death by euthanasia (7), Elevated alanine aminotransferase (ALT) (6), Seizure NOS (6). Outcome, 39 coded reports: Recovered/Normal leads at 30.8%.

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.

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.