Heartworm Disease - Monthly Prevention

Heartworm disease is a deadly but preventable condition spread by mosquitoes. All dogs and cats—even those indoors—should be on monthly heartworm prevention (HWP) for life. This simple medication also protects against intestinal parasites, reducing the need for separate deworming. We typically recommend Simparica Trio for dogs and Revolution Plus for cats.

Heartworm Testing

Dogs require a heartworm test before starting prevention and annual testing thereafter. If prevention starts after 4 months of age, a follow-up test is needed. Since heartworm disease can still develop despite prevention, annual tests ensure early detection. If your dog tests positive while on vet-purchased prevention, the manufacturer may cover treatment costs. Cats do not require routine heartworm testing unless symptoms arise.