We carry flea, tick, & heart worm preventative in-house, which means it should be available at all times. We carry flea and tick preventatives for 1 month prevention or 3 month prevention. We carry not only oral heart worm preventatives, but also injectable heart worm prevention that will last 6 months or 12 months. If there is a preventative that you prefer for your pet that we do not carry, please look on our online store here on our website. For a list of the products we carry, please click on the individual Flea Prevention, Tick Prevention, & Heart Worm Prevention links under this tab.