Preventives

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	Sarcoptic Mange Mites	Minimum Age/ Weight	Safe to Use During Breeding/ Lactation	Food Allergen Considerations
Oral Administration (monthly tablets and chews)
Ivermectin + pyrantel pamoate	HEARTGARD^® Plus (Boehringer Ingelheim) Tri-Heart^® Plus (Merck)	X				X^a	X^b					6 weeks/ no minimum weight	Yes	Beef
Ivermectin + pyrantel pamoate	Iverhart Plus^® (Virbac)	X				X^a	Xb					6 weeks/ no minimum weight	Yes	Pork Liver
Ivermectin + pyrantel pamoate + praziquantel	Iverhart Max^® (Virbac)	X				X^a	X^b		X^h			8 weeks/ 6 lbs	Not Evaluated	Pork liver Artificial Beef
Milbemycin oxime	Interceptor^® (Elanco) MilbeGuard^® (Ceva) Milbehart™ (Virbac)	X				X^c	X^b	X^d				4 weeks/ 2 lbs	Yes	Beef
Milbemycin oxime + praziquantel	Interceptor^®Plus (Elanco)	X				X^c	X^b	X^d	X^f			6 weeks/ 2 lbs	Not Evaluated	Chicken
Milbemycin oxime + lufenuron	Sentinel^® Flavor Tabs (Merck)	X		X^j		X^c	X^b	X^d				6 weeks/ 2 lbs	Yes	Artificial beef Pork/soy
Milbemycin oxime + lufenuron + praziquantel	Sentinel^® Spectrum^® (Merck)	X		X^j		X^c	X^b	X^d	X^f			6 weeks/ 2 lbs	Not Evaluated	Beef
Milbemycin oxime + spinosad	Trifexis^® (Elanco)	X		Xⁿ		X^c	X^b	X^d				8 weeks/ 5 lbs	Use with caution	Artificial beef Pork liver/ hydrolyzed soy
Moxidectin + afoxolaner + pyrantel	NEXGARD^® PLUS (Boehringer Ingelheim)	X		Xⁿ	X⁶	X^a	X^b					8 weeks/ 4 lbs	Not Evaluated	None
Moxidectin + sarolaner + pyrantel pamoate	Simparica^® Trio (Zoetis)	X		X^k	X^l	X^m	X^b					8 weeks/ 2.8 lbs	Not Evaluated	Pork
Injectable Administration (every 6 or 12 months)
Moxidectin	ProHeart^® 6 (Zoetis)	X				X^o						6 months/ 5 lbs	Yes
Moxidectin	ProHeart^® 12 (Zoetis)	X				X^o						12 months/ 5 lbs	Yes
Topical Administration (monthly spot-on)
Moxidectin + imidacloprid	Advantage Multi^® (Elanco) IMOXI^™ (Vetoquinol USA) PARASEDGE^™Multi (Virbac) Midamox^™ (Norbrook)	X	X	Xⁿ		X^p	X^q	X^d			X^r	7 weeks/ 3 lbs	Not Evaluated
Selamectin	Revolution^®(Zoetis) Paradyne^®(Vethical) Senergy^™ (Virbac) Selarid^™ (Norbrook) Revolt^™ (Aurora)	X		X^z	X¹					X^u	X^r	6 weeks/ no minimum weight	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 Age/ Weight	Safe to Use During Breeding/ Lactation	Food Allergen Considerations
Oral Administration (monthly tablets and chews)
Milbemycin oxime	Interceptor^® (Elanco) MilbeGuard^® (Ceva) Milbehart^™ (Virbac)	X				X^c	X^e			6 weeks/ 1.5 lbs	Not Evaluated	Beef
Topical Administration (monthly spot-on; Bravecto PLUS is every 2 months)
Moxidectin + imidacloprid	Advantage Multi^® (Elanco) IMOXI^™ (Vetoquinol USA) PARASEDGE^™Multi (Virbac) Midamox^_™ for Cats (Norbrook)	X		Xⁿ		X^s	X^t		X^u	9 weeks/ 1.5 lbs	Not Evaluated
Moxidectin + fluralaner	Bravecto^® PLUS (Merck)	X		Xⁿ	X^v	X^s	X^t			6 months/ 2.6 lbs	Not Evaluated
Esafoxolaner + eprinomectin + praziquantel	NEXGARD^® COMBO (Boehringer Ingelheim)	X		Xⁿ	X⁴	X^g	X^e	X⁵		8 weeks/ 1.8 lbs	Not Evaluated
Selamectin	Revolution^®(Zoetis) Paradyne^® (Vethical) Revolt^™ (Aurora) Senergy^™ (Virbac) Selarid^™ (Norbrook)	X		X^k		X^m	X^e		X^u	8 weeks/ no minimum weight	Yes
Selamectin + sarolaner	Revolution^® Plus (Zoetis)	X		X^k	X²	X^m	X^e		X^u	8 weeks/ 2.8 lbs	Not Evaluated

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) Midamox™ for Cats (Norbrook)	X		Xⁿ						2 lbs	Not Evaluated

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.