Welcome to Justanswer! I am Dr. Altman and happy to assist you both today!
There are a handful of causes of urination that has blood in it:
1.) A urinary tract infection
2.) Bladder stones that traumatize the bladder and cause bleeding
3.) A bladder tumor, most likely in a senior pet
4.) Trauma- hit by car, muscle trauma of some kind
5.) Rimadyl (carprofen) maybe the culprit if it is affecting the kidneys. According to the veterinary formulary:
Mild gastrointestinal effects (e.g., vomiting, diarrhea, inappetence, etc.) or lethargy are the most likely to appear but incidence is low (<2%). Rarely, serious effects including hepatocellular damage and/or renal disease; hematologic and serious gastrointestinal effects (ulceration) have been reported. Increased risks for the development of renal toxicity include preexisting renal insufficiency, dehydration or sodium depletion.
Ideally until you are able to get to your veterinarian, please discontinue the rimadyl and increase water intake. You can do this by supplementing the dry food with water and flavoring the water (maple syrup or no salt broth for example) as well. Increasing the water intake will help "flush" out the bladder and reduce the pain associated with the bleeding.
Monday collecting a first morning sample in a tupperware container and refrigerating the sample if more than an hour old to have your vet evaluate the sample will help determine the cause of the blood in the urine.
Your vet will run a urinalysis, potentially do a urine culture to look for bacteria, an X-ray to rule out a bladder stone, and bloodwork to ensure there is not a metabolic cause or kidney issues causing the symptoms
Diagnosing the issue will help determine how best to treat the blood in the urine to get your pet comfortable swiftly
Below is more information on this condition in dogs, called hematuria (blood in urine):
If there is increased water intake, she is escalating in her discomfort with urination, lethargy or restlessness, vomiting, gums become pale or sticky then please consider a veterinary er tonight.
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