Keep your dog free from the parasites that matter by killing fleas, heartworm, ticks and intestinal worms. Kills flea infestations, as well as ticks (Brown and the deadly Paralysis Tick), for the full month. Kills fleas and ticks within 4 hours. Break the flea life cycle by killing adult fleas before they can lay eggs - no further environmental infestation. Vet grade heartworm protection with Moxidectin that kills heartworm as well as intestinal worms. Safe for puppies from 8 weeks of age.