The active ingredient in Stronghold/Revolution, Selamectin, controls American Dog Tick infestations (Dermacentor Variabilis) . Revolution is marketed to the US/Canada, so the packaging says that it covers Dermacentor Variabilis while Stronghold packaging will not say this because it is marketed to areas where this tick is not present.
By Ooitzkimoo on 29 May 2014