(Merial) Heartgard Chewables for Dogs help prevent canine heartworm disease. Heartgard Chewables contain ivermectin. Give monthly, as directed. Heartgard Chewables kill immature heartworms that have been introduced to the dogs within the last 30 days. Approved for puppies as young as 6 weeks, pregnant or breeding female dogs and stud dogs. Ivermectin.
Each Blue contains 68 mcg ivermectin.
Each Green contains 136 mcg ivermectin.
Each Brown contains 272 mcg ivermectin.
Heartworms can infect your dog without your knowledge. Each bite from an infected mosquito can introduce heartworm larvae into your dog’s bloodstream and re-infect an unprotected dog. Heartgard Plus helps protect your dog against heartworm disease in order to avoid the risk, expense and emotional toll of treatment. All dogs should be tested for heartworm infection before starting a preventative program like Heartgard.