Lack of efficacy (ectoparasite) - tick NOS

Lack of efficacy (ectoparasite) - tick NOS Reaction Insights

The FDA Center for Veterinary Medicine database currently lists 15,484 adverse event reports that reference Lack of efficacy (ectoparasite) - tick NOS as a reaction term, including 141 reports with a death outcome — a 90.0% case-fatality figure calculated across only those events where this reaction was coded. The reaction is indexed in the openFDA system under VeDDRA code 2658, the standardized veterinary dictionary used to normalize clinical signs across submitters. Because reports are voluntary and often describe multiple concurrent signs per animal, the volume here reflects reporting intensity rather than true incidence in the broader pet population.

Lack of efficacy (ectoparasite) - tick NOS appears most frequently in reports for Dog (14,827 reports), Cat (617 reports), Cattle (31 reports) — with Dog dominating at 14,827 entries. Within those species, the breeds most often named alongside this reaction are Retriever - Labrador (1,741), Dog (unknown) (1,388), Crossbred Canine/dog (1,301). These distributions are influenced both by underlying breed popularity and by how veterinarians and owners code a given clinical sign, so they should be interpreted as a reporting fingerprint rather than a pure susceptibility ranking.

The drugs most commonly co-reported with Lack of efficacy (ectoparasite) - tick NOS are Afoxolaner (4,524 reports), Fluralaner 13.64% 12-Week Chew (2,804 reports), Pyrantel Pamoate;Sarolaner (2,765 reports), Fluralaner Chew Tablets (1,566 reports), with Afoxolaner appearing alongside this reaction in 4,524 submissions. Co-reporting does not establish that any specific product caused the reaction — FDA CVM data captures temporal association only. The value of these aggregates is in flagging which therapeutic classes appear repeatedly alongside a given clinical sign, so owners and veterinarians can ask targeted questions about medications currently in use.