Drug profile

The FDA adverse-event record for Clostr Perf*2/Clos Others*4 Kb

137 adverse-event reports submitted to the FDA Center for Veterinary Medicine reference Clostr Perf*2/Clos Others*4 Kb. See the species affected, top reactions, and outcomes below.

137
adverse-event reports
87.6%
death-coded share
Cattle
most-reported species
111
Death - 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.
137
Total Reports
120
Deaths Reported
87.6%
Death Rate

Active Ingredients

Clostr Perf*2/Clos Others*4 Kb

Administration Routes

SubcutaneousUnknown

Species Affected

Cattle 137

Most Affected Breeds

Cattle (other) 72
Aberdeen Angus 25
Crossbred Bovine/Cattle 22
Holstein-Friesian also known as Holstein 8
Mixed (Cattle) 4
Cattle (unspecified) 3
Charolais 2
Simmental 1

Most Reported Reactions

Death 111
Lack of efficacy - NOS 73
Lack of efficacy (bacteria) - NOS 15
Respiratory signs 8
Death by euthanasia 7
Necropsy performed 7
Lack of efficacy (endoparasite NOS) 6
Anaphylaxis 6
Laboured breathing 5
NT - Abnormal necropsy finding NOS 5
Pneumonia 5
Lameness 5

Outcome Breakdown

Died
117 (41.5%)
Ongoing
66 (23.4%)
Recovered/Normal
48 (17.0%)
Outcome Unknown
43 (15.2%)
Euthanized
8 (2.8%)

Clostr Perf*2/Clos Others*4 Kb Adverse Event Insights

137 reports name Clostr Perf*2/Clos Others*4 Kb; 120 recorded a death outcome (87.6% of reported events, not a population-level mortality rate). Active ingredient: Clostr Perf*2/Clos Others*4 Kb. Administration routes: Subcutaneous, Unknown.

By species: Cattle (137 reports). By breed: Cattle (other) (72), Aberdeen Angus (25), Crossbred Bovine/Cattle (22).

Leading clinical signs: Death (111), Lack of efficacy - NOS (73), Lack of efficacy (bacteria) - NOS (15), Respiratory signs (8). Outcome, 282 coded reports: Died leads at 41.5%.

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.