Blood in the urine is called hematuria. It may be visible, making urine look pink, red or brown, or it may be found only during a urine test. Visible blood in the urine should be medically assessed even when it happens only once, is painless or seems to be a small amount.
Types of hematuria
- Gross hematuria: blood can be seen in the urine.
- Microscopic hematuria: blood cannot be seen but is detected by urinalysis or microscopy.
Possible causes
Hematuria can have many causes, ranging from temporary or treatable problems to conditions that require further investigation. Causes include:
- urinary tract infection or inflammation of the bladder, kidney, urethra or prostate
- kidney or bladder stones
- benign prostatic hyperplasia (enlarged prostate)
- kidney disease, including glomerular disease
- injury or a recent urinary tract procedure
- vigorous exercise
- certain medicines, including medicines that affect bleeding
- blood-clotting disorders
- cancer of the bladder, kidney or prostate
Menstrual blood can contaminate a urine sample, and some foods or medicines can change urine color without true urinary bleeding. A repeat urine test may sometimes be needed to clarify the result.
Diagnosis
Assessment usually starts with medical history, physical examination and urinalysis. A healthcare professional may ask about pain, urinary symptoms, medicines, smoking history, recent infections, exercise and previous urinary tract problems.
Depending on the findings and individual risk, additional testing may include blood tests, urine microscopy, ultrasound, CT or MRI imaging, or cystoscopy to examine the urethra and bladder. A kidney biopsy is needed only in selected cases when kidney disease is suspected and other tests do not provide enough information.
Treatment
Hematuria itself is a sign rather than a diagnosis. Treatment depends on the underlying cause. For example, an infection may require appropriate treatment, stones may need pain management or a urologic procedure, and kidney or urinary tract disease requires treatment specific to the diagnosis. Some people need monitoring rather than immediate treatment.
When to seek medical care
Visible blood in the urine should be evaluated by a healthcare professional. Microscopic blood found on a urine test may also require repeat testing or further investigation depending on age, symptoms, medical history and other risk factors.
Seek urgent medical care if you cannot urinate, are passing blood clots, have severe side, back or abdominal pain, or develop fever, shaking chills, vomiting or rapidly worsening illness. Seek emergency medical care for collapse, severe weakness, confusion or heavy ongoing bleeding. Use your local emergency medical service when symptoms are severe or life-threatening.
Do not stop prescribed anticoagulant or antiplatelet medicine without medical advice.
Related topics
Sources
- NIDDK: Hematuria (Blood in the Urine)
- MedlinePlus: Blood in Urine
- NIDDK: Cystoscopy and Ureteroscopy
Last reviewed: 4 September 2026. This page provides general health information and does not replace individual medical assessment, diagnosis or treatment.