The phrase "oral heartworm" refers to a type of medication that is given to dogs to prevent them from getting heartworm disease. It is taken by mouth as a pill or chewable tablet. Full definition
A typical oral heartworm product kills heartworm larvae that have infected your dog in the last 30 days. (trifexis.com)
We have monthly oral heartworm preventatives in combination with intestinal wormers, and we have oral preventatives in combination with intestinal wormers that also can inhibit the hatching of flea eggs. (tulsapetsmagazine.com)
Tri-Heart Plus Chewable Tablets is a once - a-month oral heartworm preventive for use in dogs to prevent canine heartworm disease and for the treatment and control of roundworms and hookworms. (medi-vet.com)