Tolerance of Biopronil Spot on after repeated single- or multiple-dose topical treatments in dogs

A variety of toxic effects of fipronil (FIP), the active substance of Biopronil Spot on®, on animals and humans has been reported and raises the need to investigate the FIP toxic effects. The objectives of the study were the evaluation of the local and systemic tolerance of Biopronil Spot on® and the assessment of its influence on haematological and biochemical blood parameters after single and multiple topical treatment in dogs. Thirtytwo mixed breed dogs were included in the study assessing the local and general tolerance of Biopronil Spot on® following single, triple and fivefold dose after spot-on multiple applications in dogs (on days 0, +28 and +56) at a dosage 134 mg for a dog weighing 10–20 kg and 268 mg for a dog weighing 21–40 kg. A physical examination and biochemical and haematological analyses were performed on the days of the study as follows: –14, –5, +3, +31, +59, +70. No visible pathological changes on the skin were observed. The biochemical and haematological indicators rarely exceeded the reference values. No influence of Biopronil Spot on® administered in single, triple and fivefold repeated doses on the assessed clinical, haematological and biochemical parameters in dogs was found under the conditions described in the study.