Best fast-acting Comfortis Chewable Tablets are fast-acting and good for cats that can't tolerate topical flea preventives. Spinosad, the active ingredient in Comfortis, starts to work within 30 ...

Best pill Simparica TRIO is our pick for the best flea and tick treatment for dogs in pill form. The fast-acting chewable tablet kills more parasites than any other oral product. It starts to work ...