Field comparison of tolerance of a collar containing 10.0% imidacloprid/4.5% flumethrin (Seresto) and a placebo collar placed on cats:

ObjectivesA collar containing 10.0% imidacloprid/4.5% flumethrin (Seresto; Bayer Animal Health) controls flea and tick infestations for 8 months and is effective in preventing transmission of Bartonella henselae and Cytauxzoon felis among cats. The purpose of this study was to compare tolerance of client-owned cats for the 10.0% imidacloprid/4.5% flumethrin collar or a physically identical placebo collar.MethodsA total of 96 client-owned cats were enrolled in the study. Cats that were systemically ill, of hairless breed or declawed in all four limbs were excluded. Cats were randomized by household to wear a placebo collar for 14 days followed by the 10.0% imidacloprid/4.5% flumethrin collar for 14 days or the 10.0% imidacloprid/4.5% flumethrin collar for 28 days. Examinations by a veterinarian were performed on days 0, 14 and 28. Owners recorded daily systemic and local health observations.ResultsAll but two cats, including one that entrapped the mandible in the collar and one that developed local pyoderm...