Ivermectin is the active ingredient in many heart worm preventative medications as well as many dewormers. In proper doses, this is a very safe and effective medication. However, when significantly overdosed, this medication can cause drooling, vomiting, weakness, heart arrhythmia's, and severe neurologic signs such as ataxia, seizures, blindness and potentially death. The most common cause of Ivermectin toxicity is from dogs ingesting horse paste dewormer. This is either from owners intentionally giving the paste as a cheaper way to "deworm" them, or from dogs accidentally ingesting the paste after a horse has spit some of it out. It is imperative that this medication be used properly and by the prescribed amount by a veterinarian. Also, if you have horses and are paste deworming, please ensure there is no way your dog can ingest the horse dewormer. Because we see horse and dog patients at Middletown Animal Hospital, we have seen the health risks associated with breeders or ranch owners "deworming" their dogs with equine paste dewormer to save money. However, dogs need more than just heartworm deworming. Ivermectin at the heartworm preventative dose is not strong enough to kill other intestinal worms like hookworms and roundworms. Because of this, another ingredients called pyrantel is included in products such as Heartgard. Middletown Animal Hospital has recently started recommending Interceptor Plus because it costs the same as Heartgard yet treats more worms: roundworms, hookworms, whipworms, and tapeworms while preventing heartworm disease! (Until now, tapeworm deworming has necessitated a second dewormer 2-4 times a year).
Remember: Heartworm preventative must be administered every month all year round without interruption in order to be effective. Exposure to mosquitoes while the animal is not protected from prevention may not provide complete heartworm prevention so don't be fooled into thinking you are saving money by administering every other month.
Remember: Cats get heartworm disease too! Middletown Animal Hospital recommends Revolution once a month for protection agains fleas and heartworm disease and treatment and control of hookworms, roundworms, and ear mites.
Remember: Heartworm products recommended and sold by Middletown Animal Hospital are guaranteed and safe! We have seen pets become very sick and even die from inadequate products found at grocery stores or feed stores.