Why Does My Pee Smell So Bad?

Medically Reviewed on 1/10/2022
Some conditions can make your pee smell bad. They include dehydration, urinary tract infection, diabetes, bladder fistula, liver disease, and maple syrup urine disease.
Some conditions can make your pee smell bad. They include dehydration, urinary tract infection, diabetes, bladder fistula, liver disease, and maple syrup urine disease.

Urine has a natural smell, and each person's pee smells different. Sometimes, you might notice that your pee smells stronger than usual. This should not be a cause for concern.

However, there are instances where a bad urine smell could signal a severe medical condition.

Asparagus is often associated with bad-smelling urine. This happens because it contains high levels of sulfurous compounds called asparagusic acid. While it doesn't affect your health in any way, high amounts of asparagusic acid can create a strong, unpleasant smell when you pee.

Most people don't realize if their pee smells different. Genetics may also contribute to "smelly pee." This condition can be managed, though, by specific medications or by avoiding foods high in asparagus acid.

Causes of unpleasant urine odor

Several underlying conditions can result in a strong or unpleasant urine smell. They include:


When you fail to drink enough fluids, your body becomes dehydrated. Dehydration causes your urine to change its natural composition. As a result, it becomes concentrated with filtered waste that contributes to the foul smell. While minor dehydration may not require medical attention, you'll need to increase your fluid intake, especially water.

However, severe dehydration can be serious and is usually characterized by extreme fatigue, mental confusion, and overall weakness. If you experience these symptoms, you should see a doctor immediately.

Urinary tract infection

Also called a UTI, this can be a major cause of unpleasant urine smell. It's often characterized by an unusual urge to urinate frequently and a burning sensation after you pee. A bacterial infection in the urinary tract usually causes UTIs. Once diagnosed, a UTI can be treated with antibiotics.


Lifestyle diseases like diabetes are another cause of unusual urine smell. People with diabetes who aren't on medication tend to develop high blood sugar levels, which, in turn, causes urine to produce a sweet odor. Untreated diabetes is dangerous and could be life-threatening, so you should see your doctor immediately if you notice a sweet-smelling odor in your urine.

Bladder fistula

One of the symptoms of bladder fistula is urine smelling or looking like stool. A bladder fistula is the result of an intestinal bacteria infecting your bladder through an injury. Such injuries can be caused by surgical procedures, Crohn’s disease, inflammatory bowel disease, or ulcerative colitis.

Liver disease

Liver disease can lead to high levels of ammonia in your urine, causing it to have an unpleasant smell. If left untreated, liver conditions can be fatal. Always see your doctor if you notice your urine has an unusual, ammonia-like odor.

Other symptoms that may indicate your liver needs attention include dark brown or orange-hued urine.

Maple syrup urine disease

This condition is rare, and no cure has been found yet. It is a genetic disease that causes urine to develop an odor similar to maple syrup. People with this condition lack the natural ability to break down the amino acids valine, leucine, and isoleucine. If left untreated, it can result in brain damage and even death.

Diagnosing urine odor

Once you visit your doctor for treatment, they will want to carry out various tests to determine if you have an underlying medical condition. These tests include:

  • Urinalysis: This procedure involves collecting and testing your urine sample to ascertain the presence of bacteria and other harmful elements.
  • Cystoscopy: The doctor inserts a thin tube with a camera inside your bladder to search for existing urinary diseases.
  • Radiological scans: This is not a popular method for diagnosing urine infection. However, it may apply in some instances.

How to prevent smelly pee

To have clear urine that only has a mild, natural smell, try these easy-to-follow solutions:

  • Drinking a lot of water to ensure that you pee regularly
  • Avoiding sugary drinks, coffee or alcohol
  • Not exceeding 10mg of vitamin B6 a day
  • Not eating a lot of garlic or asparagus

When to see the doctor

You should make an appointment to see your doctor if you experience smelly urine that persists beyond three days. Also, seek medical attention if you experience bloating, nausea, vomiting, mental disorientation, or sweet-smelling urine. These symptoms may be a result of diabetes, a liver condition, or acute dehydration.

Several factors can cause an unpleasant smell of your urine. Since it could be anything from genetics to underlying health conditions, medications, and certain foods, it is wise not to ignore this vital sign.


Pancreatitis is inflammation of an organ in the abdomen called the pancreas. See Answer
Medically Reviewed on 1/10/2022
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