What Are Some Common Causes of Blood in the Urine?

The medical term for blood in the urine is hematuria. Sometimes, it is easy to tell when there is blood in the urine based on its appearance. But that’s not always the case. If blood is present in small amounts, it may be invisible to the naked eye. 

Blood in the urine isn’t always dangerous, but it is never normal. So identifying the underlying cause is important. Below, we’ll discuss what blood in the urine looks like, its common causes, and when it’s time to see your doctor.

What does blood in the urine look like?

Blood in the urine can have many different appearances. It can look:

• Light pink 

• Bright red

• Dark red 

• Brown or brownish-red 

But hematuria is not always obvious. If there are small amounts of blood present, the urine can be its normal yellow color. This doesn’t mean you need to always worry that there may be blood hiding in your urine. The conditions that cause bleeding — like urinary tract infections (UTIs) and kidney stones — usually have other symptoms, too.

What causes blood in the urine?

Blood in the urine can be caused by several different things. A few of the causes are:

• UTI: This includes infections anywhere along the urinary tract, including the urethra, bladder, or kidney.

• Kidney stones: If a kidney stone leaves the kidney and starts to travel down the urinary tract, it can cause some bleeding as it moves. 

• Enlarged prostate: Benign prostatic hyperplasia can sometimes cause bleeding. Though, it is more likely to cause difficulty peeing, or a weak urine stream. 

• Cancer: Prostate, bladder, and kidney cancer can all cause blood in the urine. But these are rarer causes.

• Injury or trauma: Any injury to the urinary tract can lead to some bleeding. This can range from mild trauma, from the insertion of a urinary catheter, to a serious fall that injures the kidneys. 

Certain medications may also cause blood in the urine. More commonly, these include:

• Penicillin: An antibiotic that can sometimes irritate the kidneys and cause bleeding

• Aspirin: A pain medication that changes the way your blood clots, which makes urinary bleeding more likely

• Cyclophosphamide: An anti-cancer drug that can damage the kidneys and lead to blood in the urine

• Anticoagulants: Medications, commonly referred to as blood thinners, that make any part of the body more likely to bleed

There are certain scenarios when urine may look like it has blood in it, but it doesn’t actually. It is easy to be fooled by:

• Menstruation: Someone who is menstruating may have urine that appears brown if blood mixes in. This commonly happens at the start or end of menstruation, when the blood looks more brown than red.

• Certain foods: Foods that are reddish in appearance — like rhubarb, beets, and berries — may make the urine appear red (especially if someone eats a lot of them). You may hear people refer to this as “beeturia” when it’s from eating beets.

• Certain medications: Laxatives, like senna, can cause the urine to take on a red appearance. Once the medication is stopped, it should go away.

• Rhabdomyolysis: This is a serious condition that results from rapid muscle breakdown. It can be caused by things like medications, drug use, intense exercise, trauma, or injury. When the muscle breaks down, it leads to a substance called myoglobin in the urine. And this leads to dark-red or tea-colored urine. 

Read more like this

Explore these related articles, suggested for readers like you.

13 Causes of Frequent Urination and How to Treat It

Why Do I Feel Like Peeing After I’ve Already Peed?

What Causes Clear Urine — and When Is It a Problem?

Urinary Tract Infection (UTI) Symptoms: What Does a UTI Feel Like?

View more

When to see your doctor

If you see blood or what may be blood in your urine, you should see your provider as soon as possible to figure out the cause. 

And if you also experience any of the below symptoms, it is particularly important that you seek medical attention right away. This may mean a visit to your local emergency room, if you are unable to see your regular provider on short notice. 

These symptoms include:

• Large amounts of bright-red blood in the urine, especially if you are on blood-thinning medications

• Fever

• Muscle aches or pain

• Persistent vomiting or diarrhea

• Abdominal or flank pain

• Fatigue or disorientation

• Peeing a lot more or a lot less than usual

• Not peeing for more than 24 hours

• Inability to empty your bladder 

What to expect at your provider’s office

When you are seen by a provider, there are several different tests that can help figure out what is going on. These include: 

• Urine tests: These tests can help confirm the presence of blood, as well as check for things like infection. 

• Blood tests: These can include a complete blood count, as well as an electrolyte panel, which tests kidney function. 

• Imaging: Tests like ultrasounds and CT scans can take a closer look at the urinary tract and kidneys. But these are not always necessary to determine the cause of blood in the urine. 

In some cases, your provider may suggest you see a medical specialist called a urologist. They can run even more tests if the diagnosis is unclear. This often includes a cystoscopy, which is when they use a tiny camera to look at the bladder.

Why trust our experts?

Written by:

Cherilyn Davis, MD

Cherilyn Davis, MD, is a board-certified pediatrician in New York City. She has held local and national roles at the American Medical Women’s Association including board member of the physician division and physician chair of social media.

Edited by:

Katie E. Golden, MD

Katie E. Golden, MD, is a board-certified emergency medicine physician and a medical editor at GoodRx.

Our editorial standards

Meet our experts