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I forgot my dog's Sentinel. Should I give heartworm medicine late?

Updated on September 23rd, 2025

Pet's info: Dog | Rhodesian Ridgeback | Female | unspayed | 2 years and 7 months old

Kiera takes Sentinel every month and I cannot remember if I gave one to her in December. Should I just wait until her due date in January? It was due the 28th

1 Answer

Most Helpful Answer

Answered By Dr. Heidi DVM, CVA, CCRT, CVTP, CVSMT, CVCH

Veterinarian, Certified Veterinary Acupuncturist, Certified Canine Rehabilitation Practitioner

Published on January 1st, 2018

I would contact your veterinarian for specific advice for Kera, but I can give you the following information. The two ingredients in Sentinel are very safe and there is a moderate dosage range. You don't mention Kiera's weight, but depending on her weight, repeating Sentinel may still be within her dosage range even if you gave the Sentinel on the 28th. I would also ask your veterinarinan about when you purchased the Sentinel since that may help you determine (with the number of tablets you have left) if you gave her one last month or not. Finally, it is generally recommended to repeat heartworm medication if you are not sure you gave it since heartworms and intestinal parasites can cause significant disease.
I hope that was helpful. Thanks for using Petco Pet Education Center, formerly Petcoach.

3Pet Parents found this answer helpful

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