My dog accidentally got a double Heartgard dose. What to watch for?

If it was Heartgard, there is no cause for concern. It is an extremely safe product and very difficult to overdose. If it was a different preparation of ivermectin, a double dose may not be cause for concern unless your dog is sensitive to it or carries the MDR1 gene. Typically, a non sensitive dog requires dosing around 2000mcg/kg before clinical signs become apparent. See your vet for an exam as soon as you can if you are concerned. Bring the container of ivermectin with you. Treatment for ivermectin toxicity is supportive in nature. Monitor for vomiting, excess salivation, ataxia (wobbly gait), dilated pupils or tremors.

The good news is that Hartgard is a relatively safe drug, and it is difficult to overdose dogs with the medication. Typically, toxicity is worried about when the dog ingests 10-20 times the recommended dose. Your dog should be just fine :-)

Heartgard Plus has a very high margin of safety, so I would not expect this to cause any serious problems. I would recommend monitoring her for the next day or two to make sure that she's acting normal, but otherwise you shouldn't need to do anything different :) You can go ahead and give her next dose on April 15th as scheduled.

While this is not good, it is unlikely that your dog will suffer any ill consequences, especially if she has been treated with Heartguard before and did not have a reaction. Ivermectin has a relatively large safety margin.

Hello, thank you for using PetCoach. I understand your concern but Max should be just fine. It does not appear that he got an overdose. If he was a breed with a known sensitivity to Ivermectin I would be more worried (herding dogs, collie breeds, etc). Here is a link to Ivermectin toxicity so you can know what to watch for but I don't think he will have any issues. Usually they will present with neurological symptoms. As always, if you are worried you should take him to your vet for an exam. ( http://www.pethealthnetwork.com/dog-health/dog-diseases-conditions-a-z/ivermectin-toxicity-dogs ) The treatment will still be effective. Don't worry about that! Hope this helps. Best wishes. If you have more questions please feel free to post again.

Hello, sorry to hear about Hillary. Reports of side effects and adverse reactions with this medication are very rare and are associated with GI signs such as (vomiting, a decreased appetited, and nausea). Hillary should be able to tolerate this double dose, however if you note any of these signs persisting over 3-5 days, then have your veterinarian evaluate Hillary. You may resume her normal dosage next month. Hope this helps and best of luck.

You did exactly the right thing by calling around to vets to ask for help right away. It's always best to check when you aren't sure, and are worried about your pet. The Triheart dose that we give dogs for heart worms has very small doses of the two medications that are in it. Ivermectin is one of the medications that is in the Tri heart. The dose is 68 micrograms. Veterinarians use this medication also to treat dogs with skin mites and use a dose over 100 times the dose in one heart worm preventive tablet. Therefore, even if she would have eaten two or three boxes of the Triheart she should be very safe and there is not any risk of an overdose of the ivermectin. The other medication is called pyrantel pamoate which is used for deworming of intestinal parasites. This medication has a very large safety margin also, and can be given at 10-20 times the normal dose without any risks of toxicity. Therefore, just like with the ivermectin in the Triheart Plus, I would not expect any potential side effects either. These potential side effects could include an upset stomach, mild diarrhea, and/or vomiting. Monitor her for those side effects, and bring her into your vet in the morning if you are still concerned.