Welcome to Justanswer! I am Dr. Altman and happy to assist you both today!
I am so sorry to hear about Spunky
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
Ideally until you are able to get to your veterinarian, please increase water intake. Since she is not eating well please try white rice and lean boiled meat in small more frequent meals and add water to the mixture. In addition flavoring the water (maple syrup for example) as well. Increasing the water intake will help "flush" out the bladder and reduce the pain associated with the bleeding.
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 not interested in food then please do not push it, if she is nauseous she may start vomiting if pushed to eat but you can try pepcid (famotidine) 0.25 mg/ pound every 12 hours 15 minutes before attempts to feed to reduce stomach acids...
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