fipronil + (S)-methoprene

**Fipronil + (S)-methoprene** is a topical spot-on combination ectoparasiticide primarily used for dogs and cats to control flea and tick infestations. **Fipronil**, a phenylpyrazole insecticide, disrupts the parasites' nervous system by blocking GABA-gated chloride channels and glutamate-gated chloride channels, leading to hyperexcitation, paralysis, and death of adult fleas, ticks, and lice upon contact. **(S)-methoprene**, a juvenile hormone analog and insect growth regulator, mimics insect hormones to inhibit the maturation of flea eggs and larvae into adults, effectively breaking the flea life cycle and preventing environmental reinfestation. Applied monthly between the shoulder blades, it provides rapid kill of existing parasites within 24-48 hours and residual protection for up to 4-5 weeks, aiding in flea allergy dermatitis management and reducing transmission of tick-borne diseases like babesiosis and ehrlichiosis.

Brand names

Frontline PlusFiprofort Plus

Other names

fipronil/s-methoprene