Blood in urine (hematuria)

Seeing blood in your urine can cause anxiety. While in many instances there are benign causes, blood in urine (hematuria) can also indicate a serious disorder.

Blood that you can see is called gross hematuria. Urinary blood that's visible only under a microscope is known as microscopic hematuria and is found when your doctor tests your urine. Either way, it's important to determine the reason for the bleeding. Treatment depends on the underlying cause.

Symptoms Causes Risk factors Prevention

The visible sign of hematuria is pink, red or cola-colored urine — the result of the presence of red blood cells. It takes very little blood to produce red urine, and the bleeding usually isn't painful. If you're also passing blood clots in your urine, that can be painful. Bloody urine often occurs without other signs or symptoms.

It's possible to have blood in your urine that's visible only under a microscope (microscopic hematuria).

When to see a doctor

Make an appointment to see your doctor anytime you notice blood in your urine.

Some medications, such as the laxative Ex-lax, and certain foods, including beets, rhubarb and berries, can cause your urine to turn red. However, blood in the urine looks distinctly different.

A change in urine color caused by drugs, food or exercise may go away within a few days. But you can't automatically attribute red or bloody urine to medications or exercise; that's why it's best to see your doctor anytime you see blood in your urine.

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