fipronil + cyphenothrin

**Fipronil + cyphenothrin** is a topical combination ectoparasiticide approved for use in dogs to control and treat infestations by fleas, ticks, and chewing lice[1][5][6]. The main brand name is Parastar Plus. It may also be effective as a treatment for sarcoptic mange and is sometimes used off-label for other ectoparasitic conditions in dogs[1]. - **Mechanism of action:** - Fipronil acts primarily as an insecticide by blocking GABA-gated chloride channels in nerve cells, resulting in hyperexcitation and death of the target parasites[5][6]. - Cyphenothrin is a synthetic pyrethroid that targets voltage-sensitive sodium channels, holding them open longer and causing persistent neuronal excitation leading to paralysis and death of insects[5][6]. - This combination exhibits broad-spectrum activity, providing rapid (effect within minutes) and persistent protection (up to 4 weeks) against targeted ectoparasites. - The product demonstrates high selectivity for insect targets over mammals, and safety data show minimal adverse effects in dogs when used according to instructions[5][6]. - Developed and manufactured by Merial (now part of Boehringer Ingelheim)[7].

Brand names

Parastar Plus

Other names

fipronil with cyphenothrin