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My dog's heartworm treatment: How to schedule 2nd and 3rd doses?

Updated on September 23rd, 2025

Pet's info: Dog | Mixed Breed Small (up to 22lb) | Female | spayed | 14.6 lbs

I got my dog her Heartworm treatment July 20th and I’m Suppose to return back 1 month which is Friday August 18th which is a Saturday my vet doesn’t open on Saturday I made an appointment on the 17 which is 29 days is that okay? How would I make an appointment for the third injection?

1 Answer

Most Helpful Answer

Answered By Daniel Fonza, DVM

Veterinarian

Published on July 21st, 2018

You will need to make sure that you schedule the 2nd and 3rd injections so that they can be given within 24 hours of each other. So you will need to schedule it for a Thursday and Friday that week to ensure both injections are done back to back as per the American Heartworm Society guidelines. I would also contact your veterinarian and make sure that this is ok to schedule as well. I hope this helps guide you in the right direction. Please let me know if you have any other questions or concerns and I would be more than happy to help you further.

1Pet Parents found this answer helpful

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