Heartworm Preventives
The American Heartworm Society recommends year-round administration of medications approved by the US Food and Drug Administration (FDA) to prevent heartworm infection. Currently available preventives are listed below; as new products become available, updates will be posted at heartwormsociety.org. Consult the appropriate manufacturer for minimum age/weight, use during breeding/lactation, or other health requirements for product usage.
Scroll down for feline and ferret preventives.
Preventives for Dogs
| Dirofilaria immitis | Other Parasites Treated in Addition to Heartworm |
| |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Drug | Trade Name(s) | Tissue Stages (Larvae) | Circulating Microfilariae | Fleas | Ticks | Hookworms | Roundworms | Whipworms | Tapeworms | Ear Mites | Mange Mites | Minimum | Safe to | Food | ||
Oral Administration (monthly tablets and chews) | ||||||||||||||||
Ivermectin + pyrantel pamoate | HEARTGARD® Plus (Boehringer Ingelheim) | X |
|
|
| Xa | Xb |
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|
|
| 6 weeks/ | Yes | Beef | ||
Iverhart Plus® (Virbac) | X |
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| Xa | Xb |
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|
| Pork Liver | |||||
Ivermectin + pyrantel pamoate + praziquantel | Iverhart Max® (Virbac) | X |
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|
| Xa | Xb |
| Xh |
|
| 8 weeks/ | Not | Pork liver | ||
Milbemycin oxime | Interceptor® (Elanco) | X |
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| Xc | Xb | Xd |
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| 4 weeks/ | Yes | Beef | ||
Milbemycin oxime + praziquantel | Interceptor® Plus (Elanco) | X |
|
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| Xc | Xb | Xd | Xf |
|
| 6 weeks/ | Not | Chicken | ||
Milbemycin oxime + lufenuron | Sentinel® Flavor Tabs (Merck) | X |
| Xj |
| Xc | Xb | Xd |
|
|
| 6 weeks/ | Yes | Artificial beef | ||
Milbemycin oxime + lufenuron + praziquantel | Sentinel® Spectrum® (Merck) | X |
| Xj |
| Xc | Xb | Xd | Xf |
|
| 6 weeks/ | Not | Beef | ||
Milbemycin oxime + spinosad | Trifexis® (Elanco) | X |
| Xn |
| Xc | Xb | Xd |
|
|
| 8 weeks/ | Use with | Artificial beef | ||
Moxidectin + afoxolaner + pyrantel | NEXGARD® PLUS (Boehringer Ingelheim) | X |
| Xn | X12 | Xa | Xb |
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|
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| 8 weeks/ | Not | None | ||
Moxidectin + sarolaner + pyrantel pamoate | Simparica® Trio (Zoetis) | X |
| Xk | X7 | Xm | Xb |
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|
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| 8 weeks/ | Not | Pork | ||
Moxidectin + lotilaner + praziquantel + pyrantel | Credelio QuattroTM (Elanco) | X |
| Xn | X4 | X10 | Xb |
| X11 |
|
| 8 weeks/ | Not | Meat allergen free | ||
Injectable Administration (every 6 or 12 months) | ||||||||||||||||
Moxidectin | ProHeart® 6 (Zoetis) | X |
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| Xo |
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| 6 months/ | Yes | |||
ProHeart® 12 (Zoetis) | X |
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| Xo |
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| 12 months/ | Yes | ||||
Topical Administration (monthly spot-on) | ||||||||||||||||
Moxidectin + imidacloprid | Advantage Multi® (Elanco) | X | X | Xn |
| Xp | Xq | Xd |
|
| Xr | 7 weeks/ | Not Evaluated | |||
Selamectin | Revolution®(Zoetis) | X |
| Xz | X1 |
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| Xu | Xr | 6 weeks/ | Yes | |||
Preventives for Cats
| Dirofilaria immitis | Other Parasites Treated in Addition to Heartworm |
| |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Drug | Trade Name(s) | Tissue Stages (Larvae) | Circulating Microfilariae | Fleas | Ticks | Hookworms | Roundworms | Tapeworms | Ear Mites | Minimum | Safe to | Food |
Oral Administration (monthly tablets and chews) | ||||||||||||
Milbemycin oxime | Interceptor® (Elanco) | X |
|
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| Xc | Xe |
|
| 6 weeks/ | Not | Beef |
Topical Administration (monthly spot-on; Bravecto PLUS is every 2 months) | ||||||||||||
Moxidectin + imidacloprid | Advantage Multi® (Elanco) | X |
| Xn |
| Xs | Xt |
| Xu | 9 weeks/ | Not |
|
Moxidectin + fluralaner | Bravecto® PLUS (Merck) | X |
| Xn | Xv | Xs | Xt |
|
| 6 months/ | Not | |
Esafoxolaner + eprinomectin + praziquantel | NEXGARD® COMBO | X |
| Xn | X4 | Xg | Xe | X5 |
| 8 weeks/ | Not | |
Selamectin | Revolution® (Zoetis) | X |
| Xk |
| Xm | Xe |
| Xu | 8 weeks/ | Yes | |
Selamectin + sarolaner | Revolution® Plus (Zoetis) | X |
| Xk | X2 | Xm | Xe | X8 | Xu | 8 weeks/ | Not | |
Preventives for Ferrets
| Dirofilaria immitis | Other Parasites Treated in Addition to Heartworm | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Drug | Trade Name(s) | Tissue Stages (Larvae) | Circulating Microfilariae | Fleas | Ticks | Hookworms | Roundworms | Tapeworms | Ear Mites | Minimum Age/ Weight | Safe to Use During Breeding/ Lactation |
| Topical Administration (monthly spot-on) | |||||||||||
| Moxidectin + imidacloprid |
Advantage Multi® (Elanco) |
X | Xn | 2 lbs | Not Evaluated |
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a - Ancylostoma caninum, Uncinaria stenocephala, A. braziliense; b - Ascarids (Toxocara canis, Toxascaris leonina); c - Adult Ancylostoma caninum; d - Trichuris vulpis; e- Toxocara cati; f - Taenia pisiformis, Echinococcus multilocularis, E. granulosus, Dipylidium caninum; g - Adult & immature hookworms (Ancylostoma tubaeforme, A. braziliense); h - D. caninum, T. pisiformis; i - Adult Ancylostoma tubaeforme; j - Prevention and control of flea populations (Ctenocephalides felis); k - Treatment of flea infestations (C. felis and C. canis); l - Treatment of tick infestations, with immediate & persistent tick killing activity for 5 weeks against Ixodes hexagonus, I. ricinus, Rhipicephalus sanguineus & for 4 weeks against Dermacentor reticulatus; m - A. caninum L4 larvae, immature adults (L5) and adults; U. stenocephala adults; n - Kills adult fleas; prevention & treatment of flea infestations (C. felis); o - Larval and adult A. caninum & U. stenocephala; p - Adult, immature adult, & fourth-stage larvae (L4) of A. caninum and U. stenocephala; q - Adult T. leonina & adult & L4 of T. canis; r - Sarcoptes scabiei var. canis; s - Adult, immature adult, & L4 of A. tubaeforme; t - Adult, immature adult, & L4 of T. cati; u - Otodectes cynotis; v - Control of tick infestations due to I. scapularis, D. variabilis, Haemaphysalis longicornis; w - Adult and L4 A. tubaeforme, adult A. braziliense; x - Adult and L4 T. cati; y - Adult D. caninum, E. multilocularis; z - Kills adult fleas & prevents flea eggs from hatching for 1 month; prevention & control of C. felis infestation; 1 - Control of tick infestations due to D. variabilis; 2 - Control of tick infestations due to I. scapularis, A. maculatum, D. variabilis; 3 - Adult D. caninum and E. multilocularis; 4 - Treatment and control of I. scapularis, R. sanguineus, D. variabilis, and A. americanum infestations for one month in dogs and puppies 8 weeks of age and older, weighing >4 pounds; 5 - D. caninum; 6 - Treatment and control of I. scapularis, R. sanguineous, D. variabilis, and A. americanum infestations for one month; 7 - A. americanum, A. maculatum. D. variabilis, I. Scapularis, R. sanguineus, Haemaphysalis longicornis; 8 - Prevention of Dipylidium caninum (tapeworm) infections as a direct result of killing Ctenocephalides felis vector fleas on the treated cat; 9 - Prevention of angiostrongylosis by reduction of the level of infection with immature adult (L5) and adult stages of Angiostrongylus vasorum (lungworm) with monthly administration; 10 - adult U. stenocephala; 11 - D. caninum, T. pisiformis, and E. granulosus; 12 - I. scapularis, R. sanguineus, D. variabilis, A. americanum, and H. longicornis.
© 2025 American Heartworm Society | PO Box 1352 | Holly Springs, NC 27540 | E-mail: info@heartwormsociety.org REV 5/15/2025
