The active ingredients in Sentinel ® Spectrum ® are Milbemycin Oxime, a proven Heartworm preventative Lufenuron, which stops fleas from becoming adults and Praziquantel, effective against tapeworms (Taenia pisiformis, Echinococcus multilocularis and Echinococcus granulosus), roundworms (Toxocara canis, Toxascaris leonina), hookworms (Ancylostoma caninum) and whipworms (Trichuris vulpis). Easy to feed administer once a month after or with a normal meal to ensure adequate absorption. The beef and bacon flavored soft-chew is readily accepted by dogs six weeks of age or older. Sentinel ® Spectrum ® chewables for dogs provides protection against heartworms, roundworms, hookworms, whipworms, fleas and tapeworms.