Mucus in Urine: 7 Causes & What to Do

Clinical review: Marcela Lemos
Biomedical Scientist
August 2022

Mucus in the urine is usually a common finding, as mucus is normally produced throughout the urinary tract to line it and protect it from infection. However, excessive amounts of mucus in the urine or other changes to urine consistency or color can be a sign of a urinary or intestinal abnormality.  

Urine that contains mucus usually looks cloudy, but the best way to confirm the presence of mucus is through a urine routine and microscopy (R&M) test. This test can detect mucus filaments in the urine as well as any other abnormalities. To complete an R&M test, it is important to avoid contamination of the urine by performing adequate genital hygiene prior to collection, and by avoiding catching the first stream of urine.

The presence of some mucus filaments in the urine is normal and usually does not require treatment. However, if other abnormalities in the urine are noted, or if you have other symptoms, the doctor may recommended medications, depending on the underlying cause of the mucus. 

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Mucus is in the urine is usually caused by:

1. Normal mucus production

Mucus is a natural substance that the body produces to protect the urinary tract. It helps with the elimination of foreign invaders that can cause infection. 

What to do: A mild to moderate amount of mucus that appears thin and clear ir a normal finding. Urine tests that detect small amounts of mucus with no other abnormalities also does not require any medical intervention. However, copious amounts of mucus, or mucus that is thick, cloudy or pus-like may be a sign of infection or another condition. If you notice these symptoms, you should consult a gynecologist, urologist or family doctor for assessment and treatment as deemed necessary. 

2. Pregnancy

Mucus in the urine is common during pregnancy. The various hormonal changes in addition to nutrient or mineral losses through the urine can give the urine a cloudy appearance. Mucus production also increases in the end-stages of pregnancy, and is a sign that the body is preparing for labor. 

What to do: In most cases, more discharge is normal during pregnancy. Changes in quantity, consistency, color or odor, however, can occur and should be reported to the monitoring obstetrician. Read more about what normal pregnancy discharge looks like.

3. UTI

Mucus can also be present with urinary tract infections (UTIs), especially when the infection results in urethritis. In addition to mucus in the urine, some people may also notice symptoms like pain and burning with urination, urinary hesitancy, and a feeling of heaviness in the lower abdomen. If you are having UTI symptoms, complete our online quiz to assess your risk for an active infection.

What to do: If you suspect you may have a UTI, you should see a doctor as quickly as possible to confirm a diagnosis. Treatment usually involves the use of antibiotics. Check out other UTI medications that can be prescribed, as well as home remedies to try.

In addition, you should drink at least 2 liters of water per day, and ensure you are cleansing the genital area from front to back to prevent the introduction of more bacteria into the urinary tract. Urinating after sex can also help to prevent new infections. These teas for UTI treatment may also be a great complement to your prescribed treatment.

4. STI 

Some sexually-transmitted infections (STIs) can lead to excessive mucus production due to irritation and inflammation in the genital area. Some STIs can also result in symptoms like yellow, green, white or grey discharge, foul odor, pain and burning with urination, abdominal discomfort and pain during sex. Learn more about the most common STIs and how they are treated.

What to do: If you notice any signs or symptoms of an STI, you should see a doctor as soon as possible. Once a diagnosis is confirmed, the correct treatment can be started. It is also important to notify your sexual partner so that he/she can seek treatment, even if they do not have any symptoms. 

5. Kidney stones 

Kidney stones do not always present with symptoms, as they are able to be eliminated in the urine naturally. However, there are cases in which the stones can become stuck along the urinary tract. This triggers the kidneys to produce more mucus, which will help to lubricate the urinary tract and help to get rid of the stone. 

Stones that are stuck in the urinary tract can cause other symptoms like urinary frequency, lower back pain, difficulty urinating, nausea, vomiting and blood-tinged urine. Read more about the symptoms of kidney stones and what causes them.

What to do: If you notice any symptoms of a kidney stone, you should see a urologist to start treatment immediately. Treatment depends on the size of the stone - small stones can be eliminated with increased water intake, while larger stones may require surgical removal. 

6. Bladder cancer

Although it is rare, mucus in the urine can be one of the signs of bladder cancer. This mucus will often be accompanied by other symptoms, like blood in the urine, difficulty urinating, pain with urination, urinary frequency, abdominal pain, weight loss for no apparent reason and fatigue. See the other signs and symptoms of cancer that you should not ignore.

What to do: If you notice these symptoms, particularly unexpected weight loss and unexplained fatigue, you should see a doctor urgently for assessment. The earlier any cancer is caught, the greater the chance of cure. 

7. Intestinal disease 

Some intestinal diseases, like ulcerative colitis or irritable bowel syndrome, can cause increased mucus production in the gut. Excessive mucus can be eliminated through the stool or in the urine. 

What to do: If you suspect any bowel diseases, you should consult a gastroenterologist to rule out any illnesses and start treatment as necessary. Depending on the cause, treatment can involve medications that delay the progression of disease or control diarrhea, as well as vitamin supplements and diet changes that prevent treat fatigue or anemia. 

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Edited by Tua Saude editing team in August 2022. Clinical review completed by Marcela Lemos - Biomedical Scientist in August 2022.
Clinical review:
Marcela Lemos
Biomedical Scientist
Masters in Applied Microbiology, and skilled in clinical analysis. Bachelor‘s in Biomedicine and licensed to practice through CRBM /PE license #08598.