When Should You Give Heartgard?

Your dog needs Hartgard every month.
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A heartworm preventive can do double duty to protect Ralph from heartworm as well as a host of other parasites. Commercially available options include Heartgard, a branded version of the drug ivermectin. Generally, use ivermectin products with a dog on a monthly basis in tablet or topical form.

Every Month, After a Negative Test

Ivermectin, a successful anti-parasite medication since the mid-1980s, guards against most intestinal worms and mites, as well as some lice. If your vet recommends Heartgard for Ralph, your pup can look forward to a heartworm test before he begins taking the medication. The heartworm test is a simple blood test to ensure your dog doesn't have the heartworm antigen. If your dog tests positive for heartworm infection, the vet decides whether Ralph needs special medicine to kill the worms or if he needs a preventive to kill the immature heartworms. If his heartworm test is negative, Ralph can begin his preventive, such as Heartgard, immediately. A puppy can have his first dose of Heartgard at 6 weeks old. Give your dog his medicine as scheduled each month, and if you miss a dose, contact your vet for guidance. Finally, resist the urge to buy large animal formulations of ivermectin on the Internet or through catalogs. Though side effects to heartworm medication are rare, it is possible to give a toxic dose of the product if it's used incorrectly.