Ivermectin is used in dogs and cats to treat a variety of parasitic diseases. Learn about the safety and side effects of this pet medication. Ivermectin is used in dogs and cats to treat a variety of parasitic diseases. Learn about the safety and side effects of this pet medication. HEARTGARD ® Plus (ivermectin/pyrantel) Chewables, given orally using the recommended dose and regimen, are effective against the tissue larval stage of D. immitis for a month (30 days) after infection and, as a result, prevent the development of the adult stage. What is Ivermectin-Pyrantel - Generic to Heartgard Plus? Tri-Heart Plus Ivermectin/Pyrantel for dogs is a heartworm preventative that also controls roundworms and hookworms. Ivermectin/Pyrantel is a generic equivalent to Heartgard Plus , and requires a prescription from your veterinarian. Ivermectin is a medication used to kill many different types of parasites in dogs. It’s most commonly used in monthly canine heartworm prevention. Toxicity to this presents as lethargy, drooling, dilated pupils, disorientation. HEARTGARD ® Plus should be administered orally at monthly intervals at the recommended minimum dose level of 6 mcg of ivermectin per kilogram (2.72 mcg/lb) and 5 mg of pyrantel (as pamoate salt) per kg (2.27 mg/lb) of body weight. Ivermectin is well tolerated compared to other microfilaricidal agents (i.e., thiabendazole, diethylcarbamazine). Adverse reactions (i.e., pruritus , fever, rash, myalgia, headache) occur commonly during the first 3 days after treatment and appear to be related to the extent of parasitic infection and systemic mobilization and killing of microfilariae. How to use Ivermectin. Take this medication by mouth with a full glass of water (8 ounces or 240 milliliters) on an empty stomach at least 1 hour before a meal. Iverhart Max ® Chewable Tablets is a combination of three anthelmintics (ivermectin/pyrantel pamoate/praziquantel). The tablets are available in four sizes in color-coded packages for oral administration to dogs according to their weight (see Dosage). Tri-Heart® Plus ivermectin/pyrantel chewable tablets are recommended for dogs 6 weeks of age and older. For dogs over 100 lbs, use the appropriate combination of these tablets. For dogs over 100 lbs, use the appropriate combination of these tablets. Ivermectin Toxicity in Dogs. This toxic reaction occurs especially in dogs that are genetically hypersensitive to ivermectin, an anti-parasite medication most commonly used for heartworm prevention, or to treat ear and hair mites, which can lead to mange.