Frontline Top Spot provides convenient and effective flea and tick control for dogs weighing 89-132 lbs. Frontline TopSpot remains effective even after bathing, water inmersion, or exposure to sunlight.When you apply FRONTLINE to your pet, the active ingredient Fipronil is stored in the natural oils of his/her skin and coat. This flea medication provides your pet with protection against fleas and ticks for a month -- even after a whole lot of baths and shampoos (or as many as your pet will sit still for!). In fact, your pet can romp in the rain, splash in the surf and get soaked to his/her happy heart's content without losing any protection against fleas and ticks. Unlike other flea control products which work only after fleas or ticks have bitten your pet, FRONTLINE kills 'em soon after contact. The flea and tick life cycles are then broken because the adults die before they can lay any of their eggs. Do not reapply Frontline TopSpot for 30 days.Contains 6 doses (6 month supply)