- Bladder & urinary health
- Blood in Urine
Bladder & Urinary · Symptom Guide
Blood in Urine
What blood in your urine can mean, when it is an emergency, and the tests that rule out anything serious. Reviewed by a licensed physician at a men's health clinic in Bangkok.
- Always needs checking, often benign
- Same-day appointment in Phrom Phong
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Medically reviewed by Dr. Noppon Arunkajohnsak (Win)
Menscape Clinic
Last reviewed
11 July 2026
1 in 5
Visible-blood cases
found to have a urinary cancer in some studies
3+
Red cells per field
the microscopic-blood threshold doctors use
48–72h
Exercise blood clears
if it lasts longer, get it checked
45+
The age to act fast
urgent referral for unexplained visible blood
Key takeaways
Visible blood in your urine is never normal. Even one episode, even if it stops on its own, needs to be checked.
Most causes are benign: stones, a urinary infection, an enlarged prostate or hard exercise. But the only way to know is to test.
Painless visible blood is the most important kind to check, because it is the classic first sign of bladder and kidney cancer.
Blood with clots and trouble passing urine, or blood with fever and flank pain, is an emergency. In Thailand call 1669 or go to the nearest A&E.
Risk rises with age and smoking. Over 45, unexplained visible blood should be investigated within days, not months.
01
The two types of blood in urine
Blood in the urine (haematuria) simply means red blood cells are getting into your urine. It comes in two forms. Visible, or macroscopic, haematuria is blood you can see: the urine looks pink, red, brown or tea-coloured. Microscopic haematuria is invisible and only shows up on a dipstick or under the microscope, usually picked up on a routine test when you feel completely well.
A tiny amount of blood colours a large volume of urine, so how red it looks tells you very little about how serious it is. Some things also mimic blood without being blood at all. Beetroot, certain food dyes, and a few medicines such as rifampicin or the bladder painkiller phenazopyridine can turn urine red or orange. A simple urine test tells pigment and real blood apart.
The common causes are reassuring ones: urinary infection, kidney or bladder stones, an enlarged or inflamed prostate, hard exercise, and minor injury. Less often the cause is inflammation of the kidney, or a tumour of the bladder, kidney or prostate.
The cause men worry about most, cancer, is not the most common. But it is the reason every episode of visible blood is checked. The point is not to guess from how it looks, but to test.
Under 40
Most often a urinary infection, a kidney or bladder stone, or hard exercise. Cancer is uncommon here, though not impossible.
40 to 50
Stones and infection are still common. An enlarging prostate starts to feature, and cancer risk begins to climb.
Over 50
Benign prostate enlargement is frequent, but bladder and kidney cancer must be actively ruled out, especially in smokers.
Any age: red flag
Painless visible blood, or blood with weight loss, needs prompt investigation whatever your age.
02
What to do about it in Thailand
Go to A&E now
Blood with clots and difficulty or inability to pass urine, or blood with fever, chills and flank pain, needs emergency care. It can mean a blocked, infected kidney or clot retention. In Thailand call 1669 for an ambulance or go straight to the nearest hospital emergency department.
Painless blood? Book this week
Visible blood with no pain at all is the kind men ignore, because it often stops after a day. Do not wait for it to come back. Painless visible blood is checked promptly to rule out a bladder or kidney cause, especially after 45 or if you smoke.²
After hard exercise? Still tell a doctor
Long runs, cycling and heavy gym sessions can briefly colour the urine. It should clear within 48 to 72 hours. Mention it at your next visit, and get it seen sooner if it lasts longer, keeps recurring, or comes with pain.
The reason painless blood matters most. Bladder and kidney cancers often announce themselves with a single, painless episode of visible blood and nothing else. That is exactly why doctors take one episode seriously, even when you feel completely well.
03
What the numbers say
Most blood in urine has a benign explanation. Across large studies of adults investigated for haematuria, stones and urinary infections are among the commonest findings. But a meaningful minority have something that needs treating, and the figures differ sharply between visible and microscopic blood.
Visible blood carries the higher risk. In a classic study of 1,930 patients investigated for haematuria, urinary tract cancer was far more likely with visible blood than with microscopic blood, with roughly 1 in 5 of those with visible blood found to have a malignancy.³ That is why guidelines treat visible blood as a red flag until proven otherwise.
Microscopic blood is usually less alarming, but still worth explaining. The AUA defines it as three or more red blood cells per high-power field,¹ and stratifies your risk by age, smoking history and how much blood is present.⁴ Most people in the low-risk group turn out to have no cancer, but the test still matters, because it tells you and your doctor which group you are in.
1 in 5
Visible blood
found to have a urinary cancer in a large investigated series
~5%
Microscopic blood
far lower cancer rate, but still assessed by risk
Figures from studies of adults investigated for haematuria. Your personal risk depends on age, smoking and symptoms. Individual results vary.
04
How we find the cause
Urine test and culture
The first step. A dipstick and microscope confirm it really is blood, and a culture checks for infection. This alone explains many cases and decides what comes next.
Imaging of kidneys and bladder
An ultrasound scan, or a CT urogram for higher-risk cases, examines the kidneys, ureters and bladder for stones, obstruction or a mass. It is the main way to look at the upper urinary tract.
Cystoscopy, when indicated
A thin camera passed into the bladder inspects the lining directly, which no scan can fully replace. It is recommended when your risk profile calls for it, for example visible blood after 45.² It is done under local anaesthetic and is usually brief.
Kidney function and blood tests
Blood tests and a check for protein in the urine assess how the kidneys are working, and flag when the cause is kidney inflammation rather than the urinary tract. This guides whether you need a urologist or a kidney specialist.
05
Related conditions & guides
Common cause · guide
Kidney stones
Sharp, cramping flank pain alongside blood in the urine often points to a stone. See how stones are diagnosed and managed.
Common cause · guide
Urinary tract infection
Burning, urgency and cloudy or bloody urine can signal a UTI. Learn how infections are tested and treated.
Men over 40 · guide
Prostate health
An enlarging prostate can cause blood and changes in how you pass urine. Understand what is normal with age and what needs a check.
06
How a consultation works at Menscape
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Seen blood once? Get it checked this week.
Start on WhatsApp or LINE
Message our team and describe what you have noticed. We help you judge whether this is something to bring in soon, or an emergency to act on now.
See a doctor in clinic
A licensed Thai physician takes your history and arranges a urine test at our clinic in Phrom Phong. The first consultation is 15 minutes.
Tests and imaging
Based on your case we organise a urine culture, kidney-function blood tests and an ultrasound scan, and explain each result in plain language.
Referral pathway if needed
If you need a cystoscopy, a CT urogram or specialist care, we refer you to a trusted Bangkok hospital and coordinate the next step, so nothing gets lost between visits.
One episode is enough. You do not need the blood to still be visible, or to have it happen twice, before getting checked. If it has happened once, that is the reason to come in.
Medically reviewed by
Dr. Noppon Arunkajohnsak (Win)
Menscape Clinic, Bangkok
“I would far rather see ten men whose blood turns out to be a stone or an infection than miss the one where it is the first sign of something serious. A single episode is always worth a visit.”
- Reviewed
- 11 July 2026
- Next review
- January 2027
- Editorial standard
- Each guide is checked against the Thai FDA label and the primary literature, then reviewed by a licensed physician.
07
Frequently asked questions
Is a little blood in my urine an emergency?
Not always, but it always needs checking. Blood with clots and trouble passing urine, or with fever and flank pain, is an emergency: call 1669 or go to A&E. Painless blood is not an emergency, but it should still be seen within days.
The blood stopped after one day. Do I still need to see a doctor?
Yes. Blood in urine often stops on its own and then returns weeks later. A single episode, even a brief one, is enough reason to be tested. Waiting for it to come back can delay a diagnosis.
Could it just be from exercise?
Possibly. Hard running, cycling or gym work can briefly colour the urine, and it should clear within 48 to 72 hours. If it lasts longer, keeps recurring, or comes with pain, it needs a proper check rather than being put down to exercise.
Can food or medicine turn my urine red without blood?
Yes. Beetroot, some food dyes and certain medicines such as rifampicin or the bladder painkiller phenazopyridine can colour urine red or orange. A simple urine test tells the difference between pigment and real blood.
Does blood in urine mean cancer?
Usually not. Most cases are caused by stones, infection or an enlarged prostate. But among adults investigated for visible blood, a meaningful minority are found to have a urinary cancer, which is why every episode is checked, especially after 45 or if you smoke.
What tests will I need?
Typically a urine test and culture first, then an ultrasound or CT scan of the kidneys and bladder, kidney-function blood tests, and a cystoscopy if your risk profile calls for it. The doctor explains which you need and why.
I'm an expat or just visiting Bangkok. Can I still be seen?
Yes. No Thai residency is required. Our clinic in Phrom Phong can run the initial urine test and scans, and refer you to a partner hospital if you need a cystoscopy or specialist care.
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References
1. Barocas DA, Boorjian SA, Alvarez RD, et al. Microhematuria: AUA/SUFU Guideline. J Urol. 2020;204(4):778-786.
2. National Institute for Health and Care Excellence (NICE). Suspected cancer: recognition and referral (NG12). Updated 2023.
3. Khadra MH, Pickard RS, Charlton M, Powell PH, Neal DE. A prospective analysis of 1,930 patients with haematuria to evaluate current diagnostic practice. J Urol. 2000;163(2):524-527.
4. Loo RK, Lieberman SF, Slezak JM, et al. Stratifying risk of urinary tract malignant tumors in patients with asymptomatic microscopic hematuria. Mayo Clin Proc. 2013;88(2):129-138.
5. European Association of Urology. EAU Guidelines on Non-muscle-invasive Bladder Cancer. EAU, 2024.
6. British Association of Urological Surgeons (BAUS). Haematuria (blood in the urine): patient information. Accessed July 2026.
7. National Institute for Emergency Medicine (NIEM), Thailand. Emergency medical services line 1669.
This guide is educational information, not medical advice. Blood in the urine has many causes, some of them serious, and needs assessment by a licensed doctor. If you cannot pass urine, or you have heavy bleeding with clots, treat it as an emergency and call 1669.
This guide is part of the Menscape bladder library
Explore the condition hubSeen blood in your urine? Don't wait for it to happen again.
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