Drug profile

The FDA adverse-event record for Lasalocid

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

101
adverse-event reports
51.5%
death-coded share
Cattle
most-reported species
48
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.
101
Total Reports
52
Deaths Reported
51.5%
Death Rate

Active Ingredients

Lasalocid

Administration Routes

OralUnknown

Species Affected

Cattle 60
Unknown 25
Horse 4
Sheep 4
Pig 2
Goat 2
Turkey 1
Other 1
Dog 1
Chicken 1

Most Affected Breeds

Holstein-Friesian also known as Holstein 27
Unknown 26
Cattle (unknown) 16
Crossbred Bovine/Cattle 6
Sheep (unknown) 4
Mixed (Cattle) 4
Horse (other) 2
Jersey 2
Turkey (unknown) 1
Pig (unknown) 1

Most Reported Reactions

Death 48
Potency, Low 9
Accidental exposure 8
Recumbency 7
Lot # and /or Expiration date missing 7
Lack of efficacy (protozoa) - Coccidia 6
Diarrhoea 6
Lack of efficacy - NOS 6
Inappropriate preparation of medication 4
Anorexia 4
Product Defect, General 4
Pulmonary oedema 4

Outcome Breakdown

Died
52 (67.5%)
Outcome Unknown
14 (18.2%)
Ongoing
6 (7.8%)
Recovered/Normal
4 (5.2%)
Recovered with Sequela
1 (1.3%)

Lasalocid Adverse Event Insights

101 reports name Lasalocid; 52 recorded a death outcome (51.5% of reported events, not a population-level mortality rate). Active ingredient: Lasalocid. Administration routes: Oral, Unknown.

By species: Cattle (60 reports), Unknown (25 reports), Horse (4 reports). By breed: Holstein-Friesian also known as Holstein (27), Unknown (26), Cattle (unknown) (16).

Leading clinical signs: Death (48), Potency, Low (9), Accidental exposure (8), Recumbency (7). Outcome, 77 coded reports: Died leads at 67.5%.

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.