IntheUSA,thepyrethrins/pyrethroidshavedominatedtheover- the-counter(OTC)marketsincetheiravailabilitybeginningin1992, followed by the prescription only malathion-containing formula- tions,suchasOvide®,beginningin1971.Thepyrethrins/pyrethroids share a common target site in the nervous system, the voltage- sensitivesodiumchannel(VSSC),andactasagonisticneuroexcitants by increasing sodium current, leading to nerve depolarization and