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My senior dog is peeing blood, and antibiotics aren't working. What's wrong?

Updated on September 23rd, 2025

Pet's info: Dog | Mixed Breed Medium (23 - 60lb) | Male | neutered | 60 lbs

My husky/Shepherd mix is 14 yrs old, with hip dysplasia. Over the weekend he was dewormed. He is urinating blood. A lot of it. It appears to be mostly blood. We've had him on penicillin for two days, without change yet. How long until it should start working if it's a UTI?

3 Answers

Most Helpful Answer

Answered By Emily, DVM

Veterinarian

Published on June 12th, 2017

Antibiotics typically improve UTI signs within 1-2 days so Bakka could have something else like a stone in his urinary tract or even an issue like a prostate gland infection or rarely cancer. As the antibiotics are not working and a stone could cause him to be unable to urinate and have kidney damage, Bakka should be seen by a veterinarian.

2Pet Parents found this answer helpful

Related Answers from Veterinarians

Answered By Jacqueline Nobles, DVM, DACVECC
Veterinarian, Board-Certified Emergency/Critical Care Specialist
Typically, we begin to see improvement in symptoms within 24-48 hours if we are treating the urinary tract infection with the appropriate antibiotic. In cases that fail to respond to treatment, I strongly recommend re-evaluating the problem and ruling out other possibilities such as a low platelet count, bladder stones, resistant bacterial infection or a bladder mass. I would advise you to have Bakka examined by your veterinarian and discuss bloodwork, urinalysis with culture and abdominal ultrasound. If I had to prioritize diagnostics, I would recommend starting with a complete blood count and ultrasound. I hope he feels better soon!
1Pet Parents found this answer helpful
Answered By Rebecca, DVM
Veterinarian
If it is a UTI symptoms start to resolve within 1-2 days. If he is urinating a lot of blood I would recommend a veterinary exam. There's a good chance this is something more than just a urinary track infection bladder stones kidney disease or systemic bleeding disorders can cause urine in the blood and penicillin won't have any affect against those.
1Pet Parents found this answer helpful

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