Foamy Urine: 7 Causes & When to See a Doctor

Updated in March 2023

Foamy urine can occur for mild, non-clinical reasons, like holding your pee for too long or urinating at a rapid speed. You may also notice bubbles in your urine due to cleaning products in the toilet bowl that react with the urine.

However, in cases where you frequently notice foamy urine, it may be a sign of protein in the urine, which can happen with kidney stones or uncontrolled high blood pressure. Foamy urine with other symptoms, like burning and dark urine, may be a sign of a UTI or even dehydration. In these cases, it is very important to see your doctor to assess the cause and indicate appropriate treatment.

Foamy urine is not a sign of pregnancy, but it could indicate preeclampsia, which is a complication during pregnancy that can lead to seizures or coma if left untreated. Therefore, if you are unsure of why you are experiencing foamy urine, or if it does not resolve on its own, you should see a doctor for further assessment. 

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What causes foamy urine?

Foamy urine may be a result of:

1. Urination speed

When the bladder is too full and you don’t go to the bathroom right away, your urine may come out too quickly and create bubbles when it hits the toilet bowl. However, this type of foam in the urine usually disappears in a few minutes and is not indicative of a serious problems.

What to do: A good way to find out if the foam is because of a quick urine stream is to leave the pee in the bowl for a few minutes before flushing. If the urine bubbles disappear after a few minutes, no treatment is required.

You should avoid the habit of holding your pee for too long, however, and you should go to the bathroom whenever you feel the urge to urinate. The accumulation of urine can increase your risk of a urinary infection, kidney stones and urinary incontinence.

2. Toilet cleaning products

Some cleaning products used in the toilet bowl can react with the urine and create a froth. This does not indicate any kind of health problem.

What to do: A good way to know a cleaning product is causing urine to appear foamy is to urinate into a clean container. If the pee doesn’t foam up, then the foam was probably due to the product. If the urinate continues to be foamy, then you should go to the doctor to assess the cause.

3. Dehydration

Not drinking enough water or exercising too much can lead to dehydration, and your urine can become more concentrated and foamier as a result. Urine will also become darker in color and have a stronger, foul odor. Urine typically becomes darker in the presence of dehydration - learn more about what different urine colors mean. 

What to do: If you suspect that the foam is because of dehydration, you should aim to increase your water intake. Aim to drink about 1.5 to 2 L (or 6 to 8 cups) of water a day and increase this amount when you exercise.

4. Protein in urine

One of the main causes of frothy urine is the presence of protein in the urine. Excessive protein may occur after intense physical exercise or excessive intake of protein supplements, but it can also be a sign of a more serious health issue, like a kidney problems, untreated high blood pressure or diabetes. Learn more about what causes high levels of protein in the urine and what to do. 

What to do: Protein in the urine can be confirmed through a simple urine test, which is done by collecting a second urine stream sample and either performing a dipstick test or sending it to a laboratory for analysis. If protein is detected, the doctor may recommend a 24-hour urine collection to evaluate the amount of protein released in the urine in one day.

The doctor may also opt to check the albumin-to-creatinine ratio in the urine to assess for any changes in kidney function. He or she may also other testing to confirm or rule out hypertension or diabetes.

5. UTI

A urinary tract infection (UTI) can cause foamy urine when bacteria is also in the bladder. In addition to foamy urine, other symptoms that may arise include pain or burning when urinating, frequent urination, and blood in the urine. Learn more about other UTI symptoms and use our online symptom checker to assess your risk for a UTI. 

What to do: A urine culture test is recommended to confirm an infection. This test will also identify the bacteria responsible for the infection, which will guide the correct antibiotic to be used for treatment. Read more about UTI treatment, which can involve both medications and home remedies. 

6. Kidney problems

The kidneys job is to filter blood and produce urine, which is then eliminated from the body. Any disease or problem that affects kidney function (like a as kidney infection, kidney failure, high blood pressure or kidney stones) can cause foamy urine. Check-out our online symptom checker to assess if your symptoms are related to a kidney problem

What to do: If there is a suspected kidney abnormality, you should see your doctor for assessment to start treatment as indicated.

In addition to these causes, foamy urine in men can also be caused by the presence of semen in the urine. After sexual contact, small amounts of semen can stay in the urethra and go to the bladder when it is malfunctioning, causing foamy urine. This situation should be evaluated and treated by a urologist.

7. Semen in the urine

Foamy urine in men may be a result of semen in the urine, although this is not a common finding. This can occur when small amounts of semen enter the urethra, which can happen with prostatitis or retrograde ejaculation, leading to foamy urine.

What to do: You should see a urologist to order testing and rule out the presence of semen in the urine. If it is present, the doctor can investigate why this is occurring and initiate treatment as appropriate. 

Foamy urine and pregnancy

Foamy urine isn’t a sign of pregnancy. However, in a woman who is pregnant, foamy urine may indicate the presence of protein in the urine, which could be a sign of preeclampsia.

Preeclampsia is a pregnancy complication characterized by high blood pressure, presence of protein in the urine, and swelling of the body. If this condition is left untreated, the woman is at risk for having seizures, which could put the health of the baby at risk.

When to see the doctor

Foamy urine can be a normal finding, especially if the foam disappears within a few minutes. However if the foam remains intact and if you notice other symptoms, it may be a sign of another health condition that requires assessment. Some examples include kidney stones, a UTI or a colovesical fistula. 

Medications can also cause foamy urine, therefore you should discuss your medications with your doctor if you suspect the foamy urine is a medication side effect.