Sclerotherapy is the process by which bleeding from the kidney can be treated and stopped through a minimally invasive approach. Bleeding from the kidney is commonly due to a varicose vein (vascular ectasia) or a benign blood vessel tumor (hemangioma) in the base of the kidney. Traditional treatments have required an open surgical approach and removal of the kidney. With sclerotherapy, surgical removal of the kidney can often be avoided. Not every patient is an appropriate candidate for this procedure and careful selection is required.


Why it’s done

Your veterinarian may recommend sclerotherapy if your pet has:

  • A history of bloody urine that is not associated with a bladder infection, bladder stones, or a bladder tumor
  • A progressive anemia that is linked with persistent bloody urine

How to prepare for your pet’s procedure

Before your pet’s procedure, you will meet with one of our specialists to talk about the procedure and what to expect.

When you meet with our team, please bring a list of all medications that your pet is currently taking, including over the counter medications, vitamins, and herbal supplements. Before your pet’s procedure, you may be asked to discontinue giving certain medications that can increase the risk of bleeding.

This is a good time to ask questions about the procedure and make sure you understand the risks and benefits.

Preoperative diagnostics and tests

Before your pet’s sclerotherapy procedure the following may be indicated:

  • Abdominal ultrasound
  • Comprehensive blood tests
  • Urinalysis and urine culture
  • Clotting tests
  • Tick transmitted disease testing (ex Tick Fever)

General Instructions for the Day of Surgery

  • Give your pet nothing by mouth after midnight the night before. This means that all food and water should be withheld.
  • Please arrive for pet’s admission promptly at your scheduled arrival time.
  • You will be asked to sign both a Surgical Consent Form as well as an Estimate, indicating your understanding of the procedure, risks, and associated costs.

What happens during a sclerotherapy procedure?

Your pet will be given a general anesthetic. A lighted instrument with a camera on the end, called a cystoscope, is used to help locate the opening of the ureter in the bladder. Bleeding can generally be localized to one side or another, through direct visualization. The process of sclerotherapy involves passing a balloon catheter from the bladder up into the base of the kidney. The balloon is inflated and the base of the kidney is repeatedly filled with a combination of fluids that cauterize the source of the bleeding. The fluids are allowed to remain in the kidney for 15 minutes. The fluid is then drained and the process repeated 4 times for a total of 1 hour. A stent is placed in the ureter at the conclusion of the procedure to ensure proper draining from the kidney while it heals. The stent is often removed 4-6 weeks later.


Complications associated with sclerotherapy can include the following:

  • Persistent bloody urine
  • Discomfort or straining while urinating
  • Infection
  • Bladder or ureteral rupture (exceedingly rare complication)

After the procedure

  • Following the procedure, you will be given a phone call with an update on your pet’s recovery. A scheduled discharge will be coordinated at that time.
  • Please remove the bandage from your pet’s intravenous catheter site 10 to 15 minutes after arriving home. • Some abdominal tenderness is common for 3-5 days following sclerotherapy.
  • It is important to restrict your pet’s activity for the next 3-5 days while your pet is healing. Walks should be short and your pet should always be on a leash. Please do not let your pet rough house with other animals during this time.
  • Many patients will not eat the night following anesthesia. If your pet has not eaten after 24 hours of returning home, please call Salt River.
  • Some patients will vomit or have diarrhea following anesthesia. If the vomiting or diarrhea persists more than 24 hours, please call Salt River. In contrast, some patients may be constipated or may not have a bowel movement for up to 72 hours following anesthesia. If your pet is straining to defecate after 72 hours, please call Salt River.
  • Suture removal may be necessary in some male dogs.
  • Scooting and more frequent urinations are common for 1-3 days following the procedure, but generally improve with each passing day. If the issues continue beyond 3 days, please call Salt River.
  • An e-collar may be necessary if your pet is licking at its penis or vulva excessively.


Samples may be submitted to a number of specialized laboratories for evaluation including the following tests:

  • Bacterial cultures

The final culture results can take up to 7-10 days. Once the final results have returned and a treatment plan has been devised, our specialists will call you to discuss the findings and recommendations.

Follow up

A recheck appointment is required 7-10 days following the procedure.