Heartworm Pet Medication: Heartgard Plus and Sentinel

Side effects of Interceptor are rare, but may include digestive upset, skin eruptions or rare neurological reactions.   The only occasional client concern I have seen with this product is when their pet won’t eat it, which is rare in my experience. When used regularly (year-round), this product is nearly 100% effective.  If for any reason a pet may become heartworm or parasite positive while on this product year-round, I have heard reports that the manufacturer will offer a refund on the product to those guardians. But if you purchase Interceptor from 1-800-PetMeds, they will pay for the diagnostic & treatment costs if your pet contracts heartworms. More information on this is covered in the 1-800-PetMeds product guarantee.One of the most commonly prescribed heartworm preventatives for dogs that I’ve used for years in practice is Interceptor, whose main ingredient is milbemycin (although Interceptor has since been discontinued, Sentinel is still available). This wonderful chewable product not only prevents mosquito-transmitted heartworm disease, but also prevents and controls the most common intestinal parasites of dogs including whipworms, roundworms, and hookworms.

The other options for clients include chewable Heartgard Plus or a generic equivalent Iverhart Plus.  Often times clients will ask – Do I have to give heartworm prevention even in the winter? The answer to this question is yes and that’s because winters are becoming milder making it difficult to predict when mosquitoes will be active in many states. In addition, this pill prevents and controls other parasites that can also affect humans; so it is indeed wise to use these types of heartworm preventatives each month.

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  1. what can i use for whip worms since the medicine is out of stock at this time

  2. My dog has been on sentinel for 3 years and has never missed a dose. Recently he has tested positive for heartworms and will receive his first injection on January 20th. He has already started his antibiotics. We are saddened and upset this has happened especially since he has been on sentinel.

  3. Sorry to hear about your dog becoming positive while on Sentinel. Unfortunately, no product is 100%, which is true of any drug. However, you may want to have your local veterinarian or yourself contact drug manufacturer as some companies will at least offer full payment of the expensive heartworm treatment

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