Drug profile

The FDA adverse-event record for Sildenafil

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

63
adverse-event reports
17.5%
death-coded share
Dog
most-reported species
11
Not eating - 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.
63
Total Reports
11
Deaths Reported
17.5%
Death Rate

Active Ingredients

Sildenafil

Administration Routes

OralUnknownOther

Species Affected

Dog 62
Human 1

Most Affected Breeds

Chihuahua 10
Terrier - Yorkshire 7
Terrier - Jack Russell 4
Shepherd Dog - Australian 4
Dog (unknown) 3
Maltese 3
Shih Tzu 3
Poodle (unspecified) 2
Crossbred Canine/dog 2
Dachshund (unspecified) 2

Most Reported Reactions

Not eating 11
Lethargy (see also Central nervous system depression in Neurological) 9
Behavioural disorder NOS 7
Hyperkalaemia 7
Lack of efficacy - NOS 6
Vomiting 6
Death 6
Death by euthanasia 6
Weight loss 5
Decreased appetite 5
Diarrhoea 5
Abnormal radiograph finding 5

Outcome Breakdown

Outcome Unknown
24 (38.7%)
Ongoing
16 (25.8%)
Recovered/Normal
11 (17.7%)
Died
6 (9.7%)
Euthanized
5 (8.1%)

Sildenafil Adverse Event Insights

63 reports name Sildenafil; 11 recorded a death outcome (17.5% of reported events, not a population-level mortality rate). Active ingredient: Sildenafil. Administration routes: Oral, Unknown, Other.

By species: Dog (62 reports), Human (1 reports). By breed: Chihuahua (10), Terrier - Yorkshire (7), Terrier - Jack Russell (4).

Leading clinical signs: Not eating (11), Lethargy (see also Central nervous system depression in Neurological) (9), Behavioural disorder NOS (7), Hyperkalaemia (7). Outcome, 62 coded reports: Outcome Unknown leads at 38.7%.

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.