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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 immitisOther Parasites Treated in Addition to Heartworm 
DrugTrade Name(s)Tissue Stages (Larvae)Circulating MicrofilariaeFleasTicksHookwormsRoundwormsWhipwormsTapewormsEar MitesSarcoptic 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       Xa Xb         6 weeks/
no
minimum
weight 
Yes 

Beef

Iverhart Plus® (Virbac) X       Xa Xb         Pork Liver 
Ivermectin + pyrantel pamoate + praziquantel Iverhart Max® (Virbac) X       Xa Xb   Xh      8 weeks/
6 lbs
  Not
Evaluated
 Pork liver
Artificial Beef
Milbemycin oxime Interceptor® (Elanco)
MilbeGuard® (Ceva)
Milbehart™ (Virbac)
X       Xc Xb Xd        4 weeks/
2 lbs
 Yes  Beef
Milbemycin oxime + praziquantel Interceptor® Plus (Elanco) X       Xc Xb Xd Xf     6 weeks/
2 lbs 
  Not
Evaluated
Chicken 
Milbemycin oxime + lufenuron Sentinel® Flavor Tabs (Merck) X   Xj   Xc Xb Xd       6 weeks/
2 lbs 
 Yes  Artificial beef
Pork/soy
Milbemycin oxime + lufenuron + praziquantel Sentinel® Spectrum® (Merck) X   Xj   Xc Xb Xd Xf    

6 weeks/
2 lbs 

  Not
Evaluated
 Beef
Milbemycin oxime + spinosad Trifexis® (Elanco) X   Xn   Xc Xb Xd       8 weeks/
5 lbs
 Use with
caution
 Artificial beef
Pork liver/
hydrolyzed soy
Moxidectin +

afoxolaner + pyrantel

NEXGARD® PLUS (Boehringer Ingelheim) X   Xn X6 Xa Xb          8 weeks/
4 lbs
  Not
Evaluated
 None
Moxidectin + sarolaner + pyrantel pamoate Simparica® Trio (Zoetis) X   Xk Xl Xm Xb         8 weeks/
2.8 lbs 
 Not
Evaluated
Pork 
Injectable Administration (every 6 or 12 months)
Moxidectin   ProHeart® 6 (Zoetis) X       Xo          

 6 months/
5 lbs

Yes
ProHeart® 12 (Zoetis) X       Xo           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   Xp Xq Xd     Xr  7 weeks/
3 lbs
Not Evaluated 

Selamectin

Revolution®(Zoetis)
Paradyne®(Vethical)
Senergy (Virbac)
Selarid (Norbrook)
Revolt (Aurora)
X   Xz X1         Xu Xr  6 weeks/
no minimum
weight
 Yes

Preventives for Cats

 Dirofilaria immitisOther Parasites Treated in Addition to Heartworm 
DrugTrade Name(s)Tissue Stages (Larvae)Circulating MicrofilariaeFleasTicksHookwormsRoundwormsTapewormsEar MitesMinimum
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       Xc Xe      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   Xs Xt   Xu  9 weeks/
1.5 lbs
 Not
Evaluated
     
Moxidectin + fluralaner Bravecto® PLUS (Merck) X   Xn Xv Xs Xt      6 months/
2.6 lbs
 Not
Evaluated
Esafoxolaner + eprinomectin + praziquantel NEXGARD® COMBO
(Boehringer Ingelheim)
X   Xn X4 Xg Xe X5   8 weeks/
1.8 lbs 
 Not
Evaluated
Selamectin

Revolution® (Zoetis)
Paradyne® (Vethical)
Revolt (Aurora)
Senergy (Virbac)
Selarid (Norbrook)

X   Xk   Xm Xe   Xu

 8 weeks/
no minimum
weight

 Yes
Selamectin + sarolaner Revolution® Plus (Zoetis) X   Xk X2 Xm Xe   Xu 8 weeks/
2.8 lbs 
Not
Evaluated 

Preventives for Ferrets

 Dirofilaria immitisOther Parasites Treated in Addition to Heartworm 
DrugTrade Name(s)Tissue Stages (Larvae)Circulating MicrofilariaeFleasTicksHookwormsRoundwormsTapewormsEar MitesMinimum
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.

© 2024 American Heartworm Society | PO Box 1352 | Holly Springs, NC 27540 | E-mail: info@heartwormsociety.org                                                            REV 5/16/2024

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The days are getting shorter, the nights are cooler, leaves are starting to turn, and football season is here. But that doesn’t mean your clients can forget about protecting their pets from heartworms.

To keep this message front and center with your clients, we’re sharing a set of new posters you can print OR post on your Facebook or Instagram page.

  • To save or print a poster, just click on the image below, then click on the “download” button and save the PDF file.
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