Interceptor and Heartgard prevent heartworm and other other worms as well. Merial, the company responsible for the Frontline flea preventative, produces Heartgard. Novartis Animal Health, which makes Sentinel and Capstar flea prevention products, sells Interceptor. These products work in somewhat different ways.
Heartworm parasites afflict dogs, which are particularly susceptible, as well as cats and other animals. Interceptor or Heartgard can prevent heartworm. When it goes undiagnosed, heartworm can claim lives.
The active ingredient for Interceptor consists of milbemycin oxime. Administer Interceptor once a month to prevent heartworm, hookworm, whipworm and roundworm infections. The four different tablet sizes of Interceptor come in color-coded packages. Each dose of Interceptor provides 0.23 mg/lb. of body weight of milbemycin oxime.
Interceptor Dosage Schedule
Dogs between 2-10 lb. in body weight will benefit from the brown package, which offers a dosage of 2.3 mg. Dogs between 11-25 lb. take pills from the green package, which offers a dosage of 5.75 mg. Dogs between 26 lb.-50 lb. in body weight will benefit from the yellow package, which offers a dosage of 11.5 mg. Finally, dogs that are 51 lb. or larger will benefit from the white package, which offers a dosage of 23.0 mg.
HeartGard's active ingredients are ivermectin and Pyrantel. Administer the HeartGard heartworm preventative monthly to prevent heartworm, round worm and hookworm. HeartGard, unlike Interceptor, does not work to prevent whipworm. HeartGard comes in three different dosage sizes, which are available in 6-dose packages and 12-dose packages.
HeartGard Dosage Schedule
Choose the right dose of Heartgard. Dogs up to 25 lb. in weight should use the blue package, which offers 68 mcg of ivermectin and 57 mg of Pyrantel. Dogs between 26 lb. and 50 lb. should use the green package, which offers 136 mcg of ivermectin and 114 mg of Pyrantel. Dogs between 51 lb. and 100 lb. in weight should use the brown package, which offers 272 mcg of ivermectin and 227 mg of Pyrantel. Dogs larger than 100 lb. should receive the proper dosage by combining multiple HeartGard chewables.
Ivermectin, one of two active ingredients in HeartGard, has been shown to be dangerous to the health of certain breeds of dogs, including shelties, collie, Australian sheepdogs and similar breeds. Consult your veterinarian when choosing a heartworm preventative.