Among the antiparasitic drugs used for the control of parasitic worms (anthelmintics) that affect dogs and cats, there are four major groups based on their spectrum of activity:

• Heartworms preventatives (against Dirofilaria spp), often controlling also some roundworm species.
• Wormers against roundworms (Toxocara canis, Toxocara cati), hookworms (Ancylostoma spp, Uncinaria stenocephala) whipworms (Trichuris spp), lungworms (Angiostrongylus vasorum) and other nematodes.
• Wormers against tapeworms (Dipylidium caninum, Echinococcus granulosus, Echinococcus multilocularis, Mesocestoides spp, Taenia spp, etc).
• All-Wormers against both roundworms and tapeworms.

Active ingredients used in anthelmintic drugs

• Heartworm preventatives contain all macrocyclic lactones, mainly ivermectin, milbemycin oxime, moxidectin, abamectin or selamectin. The spectrum of activity of these active ingredients at the recommended dose for heartworm prevention is different: some are ineffective against most roundworm (e.g. ivermectin), others control a several roundworm species as well.
• Anthelmintics against roundworms contain mainly pyrantel, febantel, fenbendazole, emodepside, piperazine and in some countries also mebendazole, levamisole and a few other active ingredients.
• Anthelmintics against tapeworms contain mainly praziquantel, a few ones niclosamide or epsiprantel.
• All-wormers contain mostly mixtures of the previously mentioned active ingredients.

Wormers that control also external parasites (e.g. fleas) are shown in another section in this site (click here).

This section includes articles on the most popular heartworm preventatives and wormers used in major English-speaking countries.

You can select an article in the tables below or in the corresponding menu (not visible on mobiles).

Heartworm preventatives (partly also roundworms and tapeworms)

Additional heartworm preventatives are included in the section for drugs against both fleas and heartworms (click here)

Control of roundworms and tapeworms (excl. heartworms)

Additional wormers are included in the section for drugs against both fleas and heartworms (click here)

Control of only roundworms (excl. heartworms)

Control of only tapeworms