TropiClean Natural Flea & Tick Maximum Strength Shampoo kills fleas, ticks and mosquitoes by contact. Our maximum strength formula repels fleas for up to 7 days. This natural essential blend contains some of natures most powerful pest fighting ingredients, maximized with lemongrass and sesame oil, for long lasting effects. Powerful and effective but safe enough for routine pet baths on dogs and puppies 12 weeks and older.