(Virbac) Iverhart Max Chewable Tablets for Dogs are used to prevent canine heartworm disease and for treatment and control of hookworms and tapeworms. Iverhart Max contains ivermectin, pyrantel pamoate and praziquantel. When given monthly as directed, it is effective in helping to prevent heartworm disease. Iverhart Max kills immature heartworms that have been introduced to the dogs within the last 30 days. Iverhart Max is also effective against canine roundworms, hookworms and tapeworms. Approved for dogs and puppies 8 weeks of age and older. Ivermectin, pyrantel pamoate and praziquantel.