ExoticRx · exoticrx.com/drugs/pyriproxyfen
US brand names:Nylar, Vectra(component)
Pyriproxyfen is dosed at 1–5 mg/kg Topical q30d in dogs, per Product labels (Vectra, Activyl); FDA openFDA Adverse Event Database. Verify against current literature before clinical use.
Juvenile hormone analog that mimics insect juvenile hormone, preventing flea eggs from hatching and larvae from developing into adults. Disrupts the flea life cycle without killing adult fleas.
Extremely low mammalian toxicity. Toxic to aquatic invertebrates — keep treated animals away from water bodies. Does not kill adult fleas; combine with adulticide for complete flea control.
Species references:All Cat (Domestic) drugsAll Dog (Domestic) drugs
Each ExoticRx dose rule is graded by the strength of its primary evidence — see the editorial process.
A dog/cat sample is shown here. Cited dosing for all 2 species — reptiles, birds, pocket pets, livestock, and equine — is free on the per-species pages above. Pro adds the weight-based calculator for every species.
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View PlansSource citations and evidence levels available on the live page. Reference only — verify against current literature before clinical use.