Reaction profile

The FDA adverse-event record for locking mechanism abnormal

340 FDA adverse-event reports reference locking mechanism abnormal (VeDDRA 99015). See the species, breeds, and drugs most associated with it below.

340
reports citing this reaction
0.9%
death-coded share
Unknown
most-affected species
Omeprazole 37% Oral Paste
most-associated drug
Verify with FDA CVM →
340
Total Reports
3
Deaths
0.9%
Death Rate

Species Most Affected

Unknown 268
Dog 56
Horse 13
Goat 1
Donkey 1
Llama 1

Breeds Most Affected

Unknown 283
Shih Tzu 7
Chihuahua 7
Miniature 4
Schnauzer - Miniature 4
Terrier - Yorkshire 3
Horse (unknown) 2
Maltese 2
Pit Bull 2
Warmblood (unspecified) 2

Associated Drugs

Omeprazole 37% Oral Paste 80
Omeprazole 62
Dexmedetomidine 45
Ivermectin(1.55%)/Praziquantel(7.75%) Paste 43
Dexmedetomidine Hydrochloride 32
Ivermectin + Praziquantel 19
Ivermectin 11
Ivermectin 1.87% Paste 8
Ivermectin, Praziquantel 7
Omeprazole Paste Horses 6
Firocoxib 0.82% Oral Paste 5
Detomidine 4
Cyclosporine 4
Ivermectin 1.87% Parziquantel 14.03% 3
Firocoxib 3
Moxidectin + Praziquantel 2
Ponazuril 1
Praziquantel; Moxidectin 1
Fenbendazol Oral Paste 1
Ponazuril 150 Mg/G Oral Paste 1

Locking Mechanism Abnormal Reaction Insights

340 reports name Locking Mechanism Abnormal; 3 recorded a death outcome (0.9% of reported events, not a population-level mortality rate). VeDDRA code: 99015.

By species: Unknown (268 reports), Dog (56 reports), Horse (13 reports). By breed: Unknown (283), Shih Tzu (7), Chihuahua (7).

Most co-reported drugs: Omeprazole 37% Oral Paste (80 reports), Omeprazole (62 reports), Dexmedetomidine (45 reports), Ivermectin(1.55%)/Praziquantel(7.75%) Paste (43 reports).

Read these counts as reporting volume, not risk: per our methodology, co-reporting reflects temporal association captured in voluntary submissions, not proof that a drug caused this reaction. A widely-prescribed drug will rack up more raw co-reports at an identical true rate than a rarely-used one, so compare within similar-exposure products.

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.