The Cedarberg area has a high incidence of tick bite fever which forces me to dose my GSDs from September to February—the time that these critters are plentiful. Natural alternatives (ACV, essential oils, etc.) are less effective during these months and Wondercide is not available in SA. My dogs have no adverse reaction to the active ingredients in Line-Up (permethrin and pyriproxyfen) and it does what it's supposed to do: keep the ticks off.