01 · Overview
The short version
It can be obvious or only found on testing
Blood in urine may turn the urine pink, red, or cola-colored, but it can also be too small to see and show up only on a urinalysis.
The cause changes the next step
A urine infection, stone, prostate problem, injury, or kidney disease can all cause blood in urine, but they are evaluated and treated differently.
Pain and urinary blockage raise concern
Blood in urine with fever, back or side pain, trouble urinating, or clots needs prompt medical attention because it can signal infection or blockage.
A urine test is often the first clue
Urinalysis can check for blood and also look for protein, glucose, ketones, bacteria, cells, crystals, and casts that help narrow the cause.
02 · Care guidance
When to get help
Emergency help
- Call 911 or go to the ER now if blood in urine comes with severe side pain and fever, inability to urinate, large clots, fainting, chest pain, confusion, or extreme weakness.
- Get emergency help right away if you might be pregnant and also have severe lower belly pain, shoulder pain, dizziness, or heavy vaginal bleeding.
- Seek urgent help after a major fall, hit to the back, or other injury if blood appears in the urine.
Get advice promptly
- Contact a clinician soon if you see blood in urine more than once, if it keeps coming back, or if it happens with burning, urgency, back pain, swelling, new high blood pressure, or trouble starting urination.
- Also seek prompt care if you take blood thinners, have kidney disease, kidney stones, prostate problems, or had a recent urinary tract infection.
- If you have painless visible blood in urine, do not ignore it just because you feel otherwise well.
If there was one small episode and you feel fine, make a non-urgent appointment for a urine test and a review of possible causes, especially if it happens again.
03 · Blood In Urine
What blood in urine means
Blood in urine is a sign, not a diagnosis.
Blood in urine means red blood cells are present in the urine. Sometimes you can see the change right away. Other times it is too small to notice and is found on a urinalysis. Either way, it should not be brushed off if it is new.
A urine test can check more than blood. It can also look for protein, glucose, ketones, bacteria, cells, crystals, and casts. Those details help point toward a kidney problem, an infection, or another cause. Urine color alone cannot tell you which one it is.
Because the urinary tract includes the kidneys, ureters, bladder, prostate, and urethra, the source can be anywhere along that path. That is why the same symptom can mean very different things in different people.
- Visible blood and microscopic blood both matter.
- A repeat urine sample may be needed if contamination is possible, such as from vaginal bleeding.
- Color alone cannot confirm the cause.
04 · Blood In Urine
Likely causes and what clues go with them
The pattern of symptoms often narrows the cause better than the color does.
A urinary tract infection can irritate the bladder or urethra and may cause blood along with burning, urgency, or cloudy urine. Kidney stones can cause blood with sudden side or back pain, nausea, or pain that comes and goes. In people with a prostate, enlargement or inflammation can affect urine flow and may also lead to blood in urine.
Other causes include kidney disease, recent strenuous exercise, injury, and some cancers of the urinary tract. In older adults, blood in urine may be the first clue that more evaluation is needed, even if pain is mild or absent.
A clinician does not have to guess from appearance alone. The urine test and the rest of the symptom pattern help decide what to check next.
- Burning and urgency often point toward irritation or infection.
- Side or back pain can fit a stone or a kidney problem.
- Weak stream, dribbling, or trouble starting can point toward prostate-related obstruction.
05 · Blood In Urine
When blood in urine needs urgent help
Clots, fever, severe pain, or trouble urinating are the big warning signs.
Blood in urine with fever, chills, side or back pain, vomiting, or feeling very ill can mean a kidney infection or a blocked urinary tract. Those problems can worsen if they are not treated quickly.
Clots in the urine, inability to urinate, or severe lower abdominal pain also need urgent assessment because the bladder or urethra may be blocked. If you have a prostate and suddenly cannot start urinating or the stream becomes very weak, that can also signal obstruction.
Any blood in urine after a major injury should be checked promptly. If you feel faint, short of breath, confused, or extremely weak, treat it as an emergency.
- Do not wait at home if you cannot pass urine.
- Seek urgent care sooner rather than later if blood is paired with fever or severe pain.
- Large clots are a reason to go now.
06 · Blood In Urine
How the evaluation usually starts
The first visit is usually about the urine test, the symptom pattern, and possible sources of bleeding.
At the visit, a clinician will usually ask when the blood started, whether it is visible or only on testing, and whether you have pain, burning, fever, urinary urgency, or trouble starting urination. They will also ask about medicines that can increase bleeding and about recent exercise, illness, menstrual bleeding, stones, infections, or kidney disease.
The first test is often a urinalysis. Depending on the result and your symptoms, the next step may be a urine culture, blood tests to check kidney function, imaging such as ultrasound or CT, or a prostate exam and related testing in people with a prostate.
This matters because a brief visit can sometimes sort out whether the problem looks like infection, blockage, kidney disease, or something that needs a closer look.
- Bring a list of medicines and supplements.
- Say if the urine sample may have been mixed with vaginal bleeding.
- Tell the clinician if the blood keeps returning even when you feel okay.
07 · Blood In Urine
Why treatment changes from one cause to another
The symptom improves best when the underlying problem is treated, not just the urine color.
If a urinary infection is the cause, treatment may involve antibiotics chosen by a clinician. If a stone is causing the bleeding, the plan depends on the stone size, location, pain, and whether there is blockage or infection. If enlarged prostate or prostatitis is involved, treatment may include medicines, monitoring, or other prostate-directed care.
Kidney-related causes may need follow-up testing, blood pressure checks, and kidney function monitoring. If a medicine is contributing to bleeding, the prescriber may need to review whether the dose or choice should change.
Do not stop a prescribed blood thinner or other important medicine on your own. Stopping suddenly can also be risky.
- Treatment is cause-specific, not one-size-fits-all.
- Some causes improve, but follow-up may still be needed.
- Do not change a blood thinner without guidance.
08 · Blood In Urine
What you can do while waiting for care
Watch for worsening symptoms and keep the next visit easier to interpret.
Drink fluids normally unless a clinician has told you to limit them for heart, kidney, or another medical reason. Keep track of whether the urine stays pink, turns red, or develops clots, and note any pain, fever, or urinary changes.
If possible, save a photo of the urine color or the first sample for the visit, since the appearance can change quickly. Avoid heavy exercise until you know the cause, especially if the blood appeared after exertion.
If you menstruate, try to give a clean urine sample away from your period when possible. Some over-the-counter pain relievers can affect bleeding risk in certain people, so check with a clinician or pharmacist before using them if the bleeding is recurring or you have been told to avoid them.
- Keep a brief symptom log.
- Do not over-exercise while the cause is unclear.
- Do not assume the problem is gone just because the urine looks normal later.
09 · FAQ
Questions people ask
Can blood in urine go away on its own?
Sometimes it can, especially if the cause was minor irritation, exercise, or a short-lived infection. But it should still be checked if it comes back, becomes visible again, or shows up with pain, fever, clots, or trouble urinating. Going away once does not prove the cause is harmless.
Is pink or red urine always blood?
No. A urine test is how clinicians tell whether red blood cells are actually present. Color change alone is not enough to confirm blood, so a new, unexplained color change is worth checking even if you feel fine.
Does blood in urine mean kidney disease?
Not necessarily. Kidney disease is one possible cause, but infection, stones, prostate problems, injury, and other urinary tract issues can also cause it. The rest of the symptoms and the urinalysis help narrow it down.
Can a urinary tract infection cause blood in urine?
Yes. A urinary tract infection can irritate the bladder or urethra and may cause blood along with burning, urgency, or cloudy urine. A urine test, and sometimes a culture, helps confirm the infection.
Will drinking more water fix blood in urine?
More fluids can help if dehydration is making urine darker, but water will not treat bleeding from infection, stones, kidney disease, or another cause. Drink normally unless you were told to limit fluids.
Should I still get checked if there is no pain?
Yes. Painless blood in urine can still come from an important problem, including kidney or bladder conditions. If it is visible or keeps happening, it deserves evaluation even without pain.
10 · References
References and supporting evidence
These sources support the points identified below. Source checking is not clinical approval.
- S1: UrinalysisMedlinePlus / U.S. National Library of Medicine
Explains that urinalysis is a urine test used to look for infection, kidney problems, and other clues, and that it can check for blood and related findings.
- S2: BleedingMedlinePlus / U.S. National Library of Medicine
Explains that bleeding can be a symptom of disease and that some bleeding problems can be serious enough to need emergency evaluation.
- S3: Prostate DiseasesMedlinePlus / U.S. National Library of Medicine
Explains that prostate disease can cause urinary symptoms, including difficulty starting or passing urine, which matters when blood in urine occurs with weak stream or obstruction.
General information, not a diagnosis. This guide is not a substitute for care from a qualified healthcare professional. For an emergency, call 911 in the US or your local emergency number. Illustrations are conceptual and are not diagnostic images.