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Is 100mg doxycycline enough for my 80lb dog with ehrlichiosis?

Updated on September 23rd, 2025

Pet's info: Dog | Coonhound - blue tick | Male | neutered | 4 years and 7 months old | 85 lbs

We have adopted a street dog on the island of Utila, Honduras where we live. There is no vet but we sent blood samples to the mainland and were told our lovely 80-90 lb. hound dog has ehrlichiosis. We are ablate buy doxycycline I'm not confident about the dosage information we are getting since we can't actually speak with the vet ourselves. Is 100mg twice daily for 3 weeks an appropriate course of treatment? Or at least an appropriate amount to give a dog of that size to start?

3 Answers

Most Helpful Answer

Daniel Fonza, DVM

Answered By Daniel Fonza, DVM

Veterinarian

Published on August 17th, 2017

Hello and thank you for your post! With Ehrlichiosis I typically dose at 5mg/kg every 12 hours, which equates to roughly 200mg twice daily. The 100mg dose does seem a bit low. I typically treat for about 6 weeks as well. Based on cases your vet has seen, he / she may have a reason for dosing at the 100mg twice daily. That is what I treat Ehrlichiosis with though and is effective. If you have any other questions please feel free to contact me. I am also available via consultation.
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Related Answers from Veterinarians

  • Answered By David Elbeze, DVM, MRCVS

    Veterinarian

    Hello, Blue would need double the amount you mentioned - either 400 mg once a day or 200 mg twice a day. 3 weeks is the minimum time, in some cases treatment need to be continued for longer, it really depends what are the symptoms, how long they have lasted and how fast they disappear once treatment has been started. in severe cases prednisolone needs to be added to the course of treatment as well.

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    1Pet Parents found this answer helpful

  • I can confirm that dosage would be 5mg/pound of body weight. So in total 400-450 mgs once daily. Yes treatment is needed for at least 3 weeks of time, depending on the persistency of the infection.
    Remember to give the medication with food and a bit of water as it could damage the mucosa of the first part of the gastrointestinal tract if not swallowed correctly.

    Please do not hesitate to contact us again on the forum or by requesting a consultation if you have any more questions or to discuss it any further.

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    0Pet Parents found this answer helpful

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