Why your urine might turn red or dark brown

Science · Published 25 October 2026 Swipe more like this →

In short: Finding blood in your urine—a condition known as haematuria—can be alarming, but the cause ranges from harmless dietary choices to serious underlying pathologies. Because it can signal everything from a simple infection to early-stage cancer, understanding the distinction between common irritants and clinical risks is essential for proper diagnosis.

Haematuria occurs when blood enters the urinary tract, which includes the kidneys, bladder, and urethra. While many people assume it indicates an immediate emergency, the severity varies significantly depending on the source and underlying mechanism. For instance, some causes are benign or temporary, such as consuming beetroot, which can turn urine pink, or taking specific medications that alter its color to red or brown.

Clinical causes often involve inflammation or physical obstructions. Urinary tract infections (UTIs) frequently present with accompanying symptoms like burning pain, cloudy urine, high temperature, or a frequent need to urinate. Kidney stones are another common culprit, particularly in men over 50, who may experience sudden urges to pee, difficulty urinating, and waking up during the night to use the bathroom. Other significant conditions include glomerular diseases, an enlarged prostate, and various malignancies. Patients might also notice a distinct smell or cloudiness in their urine during an infection. Some individuals may feel unable to lie still due to persistent discomfort.

Because haematuria can be a sign of cancer—which is often easier to treat when detected early—medical professionals emphasize that self-diagnosis is risky. A GP typically evaluates symptoms such as side pain, nausea, or groin discomfort to determine the source. Diagnostic steps may include urine samples, blood tests, rectal examinations, or vaginal exams depending on the patient's anatomy. If an infection is confirmed, antibiotics are a standard treatment, but persistent issues often require specialist referral for deeper investigation. Doctors may perform a rectal examination or a vaginal exam as part of the initial assessment. They will look for specific indicators like pain in the lower back or sides.

General information, not professional advice. Spotted an error? Flag the card or see corrections and complaints.

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