Blood in the urine, or hematuria, may make the urine look red, brown, or pink. There may be blood every time you urinate or just from time to time. You cannot always see blood in the urine, but it will show up in a urine test.

Blood in the urine may be serious. It should always be checked by a doctor. Your doctor may recommend more tests, including an X-ray, a CT scan, or a cystoscopy (which lets a doctor look inside the urethra and bladder).

Blood in the urine can be a sign of another problem. Common causes are bladder infections and kidney stones. An injury to your groin or your genital area can also cause bleeding in the urinary tract. Very hard exercise—such as running a marathon—can cause blood in the urine. Blood in the urine can also be a sign of kidney disease or cancer in the bladder or kidney. Many cases of blood in the urine are caused by a harmless condition that runs in families. This is called benign familial hematuria. It does not need any treatment.

Sometimes your urine may look red or brown even though it does not contain blood. For example, not getting enough fluids (dehydration), taking certain medicines, or having a liver problem can change the color of your urine. Eating foods such as beets, rhubarb, or blackberries or foods with red food coloring can make your urine look red or pink.