Bad Smelling Urine: Causes, Treatments, and When to See a Doctor

Urine usually has a light odor, but bad smelling urine can be due to dehydration or an infection in your urinary tract. Certain foods that you consume such as asparagus or protein-rich foods can also cause strong smelling urine like ammonia or sulfur. Other conditions can cause your pee to smell musty or have a sweet aroma. Thankfully, smelly urine is not always a cause for concern, especially if it only occurs occasionally.

Conditions affecting your urinary system that make your urine smell bad usually accompanied by other symptoms. You may find that passing smelly pee causes a burning sensation and your urine looks cloudy. Sometimes, increasing your fluid intake is enough to get rid of smelly urine symptoms.

Frequently passing urine with a strong odor or with foul smell may be a sign that you need to see a doctor.

If you want to know what causes your pee to smell really bad, please read on to find the answer.

Symptoms of Smelly Urine

Healthy urine should be a light pale color that only has a very faint, hardly-detectable odor. Symptoms of a urinary problem are usually associated with pee that smells bad and also looks bad.

Smelly urine: common symptoms

• Burning sensation when you pass smelly or stinky urine.
• Intense urge to use the bathroom but only peeing small amounts.
• Fever and chills if a urinary tract infection has reached your kidneys.
• Cloudy urine.
• Lower back pain and possible abdominal cramping.

What does bad-smelling urine smell like?

• Pee that smells of ammonia if there is a high protein content in it.
• Urine that smells weird, like coffee or other strong-tasting foods or beverages.
• Urine with a sweet aroma.
• Pee with a distinct fishy aroma due to vaginal infections.
• Sulfur-like smell that resembles rotten eggs.

Bad smelling Urine: Overview of Causes and Treatment Options

How Long Strong-Smelling Urine Can Last

Urine that has a distinct odor due to consuming certain foods or supplements should last a day or two.

Infections in the urinary tract can make your pee stinky for a few days until the infection is treated.

Conditions that can Cause Strong Urine Odor (Short Overview)

• Your diet can make your pee smell funny or weird depending on what you eat and how often you eat it.
• Diabetes causes strange-smelling urine because of increased levels of glucose in pee.
• Any kind of urinary infection may turn urine cloudy and smelly.

Who can Suffer from Smelly Pee?

• Women often have very strong-smelling fishy urine because of urinary tract infections.
• Men can get UTIs too and these are more common after the age of 50.
• If you have diabetes, you may notice that you have sweet-smelling urine.
• Anyone’s pee can smell stronger in the morning because urine is more concentrated.

What Should You do if You Have a Foul-Smelling Urine?

• Make sure that you drink plenty of water daily to flush toxins from your liver and kidneys and prevent dehydration.
• See your doctor promptly if you continue to have a strong urine odor which is cloudy or have unusual dark color or with accompanying symptoms such as lower abdominal pain, nausea or fever.

What It Can Mean if You Have Smelly Urine – Common Causes of Bad Smelling Urine

Let’s look in more detail at the many causes of urine that smells bad, musty, like ammonia, or has a distinctly foul smell.

Dehydration

Dehydration due to not drinking enough fluids, or as a result of diarrhea or vomiting can cause your pee to smell bad and look dark.

According to Dr. Melissa Conrad Stöppler on MedicineNet, dehydration can cause your urine to become more concentrated. This will result in a distinct ammonia smell in urine.¹

The consequences of dehydration also include fatigue, headaches, dizziness and dry skin and mouth. Ideally, you should drink enough fluids daily so that your pee is a pale straw color with only a very faint odor.

Certain foods, drinks or supplements

Compounds in certain foods can be excreted in your pee causing it to have a strong smell and different color.

For example, the journal Chemical Senses reported that asparagus can cause urine to smell like sulfur. Some people say that this makes their pee smell like rotten eggs or cooked cabbage. Scientists noted that the ability to smell sulfur compound in urine isn’t common to everyone.²

Other reasons for your diet causing bad smelling urine can include eating a high-protein diet³ or taking vitamin B6 supplements.⁴

Urinary tract infection (UTI)

The presence of bacteria in your urinary tract can cause an infection that can result in urine with a strong odor. The stinky pee might also be accompanied with pain or burning sensation when peeing.

A systematic review of a number of studies into UTIs found that malodorous urine is present in the majority of urinary infections. Along with urine that smells “offensive,” a UTI can cause any of the following symptoms:⁵

• Turbid urine that appears cloudy and murky
• Lower pelvic pain and cramping
• Discomfort or burning sensation when passing urine
• Discharge that has a bad smell
• White blood cells in urine
• Evidence of nitrites in urinary samples

If you suffer from urinary tract infection, you can try these natural home remedies at the first sign of an infection to prevent the infection from developing.

Kidney infection

Very strong-smelling urine could be a sign of a kidney infection when a UTI has reached your kidneys. In many circumstances, you will also have cloudy urine with odor.

Doctors from the Mayo Clinic say that smelly urine in men and in women is common with kidney infections. The infection usually starts in the bladder and then travels to the kidneys. Other symptoms of a kidney infection can include:⁶

• Back pain where the kidneys are located
• Signs of blood in your urine (hematuria)
• Cloudy pee that causes a burning sensation when you use the bathroom
• Fever, chills, nausea and vomiting

Drinking plenty of fluids daily is a great habit to keep your kidneys in good health and get rid of toxins from your urinary system.

You need to see a doctor for any symptoms of a kidney infection.

Kidney stones

Sharp pain in your middle back or flank along with pee that smells really bad could be a sign of kidney stones.

Doctors from the National Institutes of Health report that kidney stones can cause a lot of pain if they move within your kidney or pass into your ureter. They may also cause your pee to look pink or red because of blood in it, as well as having painful or frequent urination. You may also experience fever, chills, nausea and vomiting.⁷

Drinking diluted apple cider vinegar is an effective way to help dissolve kidney stones naturally and get rid of the discomfort.

Cystitis

Cystitis is an infection of the bladder wall which can cause bad smelling urine.

Doctors from the National Health Service say that symptoms of cystitis may clear up in a few days. However, chronic bladder inflammation can cause a persistent strong odor in urine. Cystitis can also make it sore when you urinate, turn your pee a dark amber color, and cause lower abdominal pain.⁸

If cystitis causes severe symptoms such as evidence of blood in your urine or general feeling that you are unwell, then you should get a checkup at your doctors.

Low-carb diets

You might find that your urine develops a strong weird odor if you are on a low-carb diet that is high in protein.

The reason for sweet smelling urine on a high protein diet is due to the presence of ketones in your urine and blood. The Journal of the American Dietetic Association reported that low-carb diets cause an increase in serum ketone in urine. This can even cause your breath to have a sweeter odor.⁹

Although cutting carbs from your diet can help to lose weight fast, you should not forget the important role complex carbs play in keeping you healthy.

Diabetes

If you have noticed that your urine has become sweet smelling, you should check your blood sugar levels.

Doctors from the National Health Service says that one of the signs of diabetes is urine with a strong sweet smell and feeling thirsty. You may also notice that you have to urinate more than usual.¹⁰

In some cases, it may be possible to control type 2 diabetes through diet and having a healthy lifestyle. Losing excess weight, improving your diet and being physically active are some of the ways to prevent type 2 diabetes.

Diabetic ketoacidosis

When your urine is sweet smelling and you have excessive thirst, it could mean that your diabetes needs to be controlled better.

According to doctors from the Mayo Clinic, diabetic ketoacidosis is a potentially serious complication of diabetes.¹¹ Diabetic ketoacidosis occurs when ketones in the bloodstream reach dangerously high levels. This can cause strong-smelling urine with a sweet, fruity smell.

Liver disease

Having strong smelling pee that has a distinct musty aroma to it can be a sign of liver disease.

According to the British Journal of Medical Practice, liver disease can also cause a strong ammonia smell in urine.¹²

However, symptoms of liver disease are more than just urine that smells bad. Liver dysfunction can also cause dark urine, swelling of the legs, jaundice, and itching all over the body. You may also experience persistent upper right abdominal pain where the liver is located.

It’s important to maintain your liver in top condition, avoid these common habits that damage your liver and be familiar with the early signs of liver disease.

Reasons for Smelly Urine in Women

There are a number of reasons why women can pass urine that has a strong odor. Of course, UTIs are a common reason for smelly urine in women. What else can cause odd smelling pee?

Pregnancy

Although pregnancy in itself doesn’t make urine smell bad, pregnant women are at greater risk of a urinary tract infection.

Dr. Emilie Katherine Johnson, an assistant professor of urology, says that hormonal changes and changes to the uterus can result in UTIs during pregnancy. Also, a large belly during pregnancy can make personal hygiene difficult and therefore contribute to bacterial infections of the urinary tract.¹³

Symptoms of urinary infections during pregnancy can include foul-smelling urine, flank pain, frequent need to pee, and blood in urine (hematuria).

Menopause

The menopause often results in thinning and drying of the vaginal walls that can lead to an increased risk of urinary tract infections.

Doctors from the Mayo Clinic describe this condition as vaginal atrophy. One side effect of vaginal atrophy is symptoms of vaginal or urinary infections.¹⁴ These conditions have the risk of causing pungent urine.

Smelly Urine in Men Only

Although men can also experience bad smelling urine from a urinary tract infection, this is much rarer than in women. Also, kidney infections, diabetes, or dehydration can cause stinky urine in men as they do in women. What can cause smelly urine in men only?

Prostate problems

One reason why men can have foul smell urine is if they have symptoms of an enlarged prostate.

Researchers from the National Institutes of Health report that an enlarged prostate can press on the urethra and cause problems with the urinary system. This can result in cloudy smelly urine, frequent and urgent need to pee, getting up during the night to pee, and pain after ejaculation.¹⁵

Inflammation of the prostate can also lead to showing signs of a UTI in men.¹⁶

Other Causes of Having Bad Smelling Urine

In rare cases, constantly passing urine that has a musty odor or smells strange could be due to a genetic or rare disorder.

Phenylketonuria

Phenylketonuria (PKU) causes a buildup of phenylalanine (an amino acid) in the body that gives urine a pungent musty smell. Usually, newborns are routinely screened for PKU, and a PKU diet can help to reduce symptoms.¹⁷

Trimethylaminuria

The journal Clinical Biochemist Reviews says that trimethylaminuria is a rare disorder that causes urine to smell like fish. A person with trimethylaminuria may also emit fishy body odors through their skin or breath.¹⁸

Maple syrup disease (MSUD)

Maple syrup disease causes a distinct sweet smell in urine. Maple syrup disease can be present at birth and will cause an infant’s urine to look and smell like sweet maple syrup.¹⁹

Does STD Cause Bad Smelling Urine?

If you have musty smelling urine or pee that smells of ammonia, does it mean that you may have a sexually transmitted disease?

Sexually transmitted diseases (STDs) won’t cause your urine to smell bad. The reason that some may think STDs cause pee to have a fishy, bad odor is that certain STDs cause smelly vaginal discharge.

Doctors from the Mayo Clinic report that some STDs will cause greenish vaginal discharge that gives off an offensive odor. You may also have a burning sensation when peeing as well as genital itching.²⁰

So, the reason for noticing a strange smell when you urinate when you have an STD is probably due to smelly genital discharge.

Does Bacterial Vaginosis Cause Smelly Urine?

Other vaginal infections may also give the impression that you are passing bad-smelling urine. However, as with STDs, the reason for the malodorous urine smell is probably due to abnormally foul vaginal discharge.

For example, Dr. Melissa Conrad Stöppler on eMedicineHealth reports that bacterial vaginosis (BV) can cause fishy vaginal discharge. If you have a bacterial vaginal infection, your urine may smell like fish but the smell is probably odor from discharge.²¹

Pelvic inflammatory disease (PID) will also cause strong-smelling vaginal discharge that can seem to make your pee stink.²²

Do Yeast Infections Cause Bad Smelling Urine?

Vaginal thrush causes a white thick discharge that usually doesn’t have a distinct odor. So, if you have a vaginal yeast infection along with urine that smells bad, it could be a sign of a urinary tract infection or something else.

How to Treat Smelly Urine

Treating the symptoms of urine that has a strong pungent smell depends on the cause. Sometimes, increasing the amount of water you drink can help to flush toxins and germs from your urinary system.

You could also try drinking large quantities of cranberry juice to help prevent bacterial infections in your urinary system. Studies have shown that cranberries contain a compound that prevents bacteria from sticking to your urinary tract.²³

When to See a Doctor

Bacterial or viral infections that affect your bladder, kidneys, or urethra can quickly develop into serious complications. Therefore, you shouldn’t wait for long if your urine continues to smell like ammonia, rotten eggs, or have a musty aroma.

Dr. Minesh Khatri on WebMD recommends seeing a medical professional for odd-smelling urine in the following circumstances:²⁴

• Your pee smells really bad and you have back pain or flank pain
• You have a constant thirst and your urine has a sweet aroma to it
• You have signs of smelly pee along with a fever and nausea or vomiting.

Related articles:

• What Can Your Urine Tell You about Your Health
• Ammonia Smell in Urine: Causes and What to Do About It
• How to Treat Urinary Tract Infection (UTI) Naturally According to Science