Smelly Pee? Here’s What It Means

Most of the time, peeing is … well, hardly a notable experience. But then there are days when the urine flows and your nose immediately picks up a certain funkiness.

Consider it a whiff of information, as the smell of your urine can offer important insight into what’s happening inside your body.

Let’s learn how to sniff out the clues with urologist Petar Bajic, MD.

Why does your pee smell?

Most urine odor can be explained simply by diet, vitamins, medications and hydration levels. But sometimes, that malodorous stream serves as a warning sign of an underlying medical issue that deserves attention, notes Dr. Bajic.

He runs through some of the most common aromas and what they mean for your health.

Pee that smells like ammonia

If you detect a hint of ammonia in your urine, it could be a sign of a urinary tract infection (UTI). The odor suggests that bacteria may be swimming around in your urinary system, most likely in your urethra, kidneys or bladder.

Urine showing signs of a UTI may also be cloudy or even a bit bloody. Peeing may become painful, too — a symptom made even worse by the fact that you may feel the need to urinate more often. A fever and mental confusion are other telltale accompanying signs.

If you have multiple symptoms, schedule a visit with a healthcare provider.

UTIs are pretty common, sending approximately 10 million Americans to a healthcare provider every year for antibiotic treatment, says Dr. Bajic. Women and people assigned female at birth and older adults are more prone to getting the infection.

Other potential causes of urine that carry the whiff of ammonia include:

• Kidney stones or kidney disease.
• Liver disease.
• Menopause.
• Prostate infection.
• Sexually transmitted infections such as chlamydia. (The symptoms here are similar to a UTI, with one noticeable difference: The addition of a pus discharge.)

An ammonia-like odor can also be linked to dehydration and certain foods and vitamins. So, if the smell pops up and disappears quickly, there’s little reason for concern. But if it lingers, get checked by a medical professional.

Fruity or sweet-smelling pee

Pee with a sugary or fruity fragrance can serve as a warning sign of diabetes or hyperglycemia (high blood sugar), says Dr. Bajic. The sweet smell comes from your body unloading excess glucose, or sugars.

In children, particularly newborns, sweet-smelling tinkle might indicate maple syrup urine disease. This rare, life-threatening metabolic disorder prevents the body from breaking down specific amino acids found in food.

The underlying message here? Urine that smells sweet shouldn’t be ignored. Check in with a healthcare provider.

Foul-smelling pee

There are plenty of innocuous reasons for pee to have notes of sulfur, like asparagus, garlic or onions. But if you haven’t recently taken a trip to Flavortown, foul-smelling urine could indicate one of two rare metabolic disorders.

Trimethylaminuria, also known as TAMU or fish odor syndrome, is a rare condition in which your body is unable to process trimethylamine — which, as it happens, is a particularly stinky chemical. The unfortunate result: Pee, breath and sweat that smells like, you guessed it: rotting fish. This condition can be inherited or acquired. While it’s an unpleasant condition, it isn’t especially dangerous.

The opposite is true of tyrosinemia, which has three distinct types (type I, II and III). Infants with this (extremely rare) genetic disorder can’t break down an amino acid called tyrosine, which is foundational to most proteins. The resulting tyrosine buildup can cause a wide range of severe complications. Tyrosinemia is exceedingly rare, but if your infant’s urine is foul-smelling, you should talk to your baby’s pediatrician anyway, just to be safe.

Why else does urine smell?

For the most part, urine carries very little odor. The reason why is simple: It’s about 95% water. The remaining amount is mostly waste products — calcium, nitrogen, potassium and more — which get filtered by your kidneys. That said, there are several other reasons your pee may smell:

You’re dehydrated

If you’re dehydrated, the percentage of water in your pee drops and the filtered waste takes a more prominent role. That creates a stronger smell, explains Dr. Bajic. (Dehydration also turns your urine a darker color, but that’s a different discussion.)

What you’re eating

Asparagus is infamous for giving urine a pretty strong sulfur smell. Your body converts an acid in asparagus into a sulfur-containing compound, which creates that pungent result.

Brussels sprouts, fish, cumin, onions and garlic also can add a certain zest to urine.

What you’re drinking

Coffee and soda drinkers may recognize a certain brewed aroma during a bathroom break. Speaking of brews, alcohol can also make your pee smell.

What you’re taking

Medications and supplements can contribute a specific scent to pee. Vitamin B6 is particularly well known for lending a certain musk to urine, as are several drugs used in chemotherapy. Supplements that contain lots of thiamin (vitamin B1) or choline have a similar effect.

Other medical issues

The conditions we’ve already discussed are just the tip of the smelly-pee iceberg. Other conditions that can affect the potency of your pee’s smell include bladder inflammation (cystitis), bacterial vaginosis and vaginal yeast infections, among others. Some people even notice a change in their urine’s smell during pregnancy!

How do I stop my pee from smelling?

“Occasional bouts of smelly pee are completely normal,” Dr. Bajic reassures. “It reflects the life you’re living.”

While it may be natural for pee to smell a bit ripe at times, that doesn’t mean you have to like it! Depending on what’s causing the problem, you may be able to do something about it.

Don’t hold it

Everybody loves the little dance you do when you really have to pee. But it and other delay tactics aren’t great for your bladder. It works best when you’re emptying it out early, often and completely.

When you answer the call of nature as intended, Dr. Bajic notes that it’s less likely you’ll struggle with issues like UTIs, urinary retention, bladder stones and more.

Adjust your diet

If you’re really concerned about the way your pee smells and your provider has given you a clean bill of health, the next logical step is tweaking your diet.

Start by upping your water consumption and reducing your intake of coffee, soda and booze. From there, experiment with eliminating foods that are known to give pee a stench. If you’re satisfied with the results and don’t mind making substitutions, that may be the end of your pee problems.

Talk to your provider about your medications

Depending on your health situation, you may be able to reduce or replace the medications, vitamins and supplements perfuming your pee. But the only person who can tell you if that’s a safe move is your provider. If you’re worried enough about the way your urine smells, they should probably be aware of it anyway. Let them know what’s happening at your next visit and how long it’s been going on.

If you’re experiencing other symptoms, be sure to mention them, too, Dr. Bajic advises — it will help your healthcare team determine whether there’s an underlying health issue that needs attention.

The bottom line

There’s usually a pretty basic explanation for urine that smells a bit different. It’s just the way your body functions, reiterates Dr. Bajic. In most cases, that funk should disappear within a day or so.

But if the smell stays and is accompanied by other symptoms, it’s something that deserves further investigation. Don’t ignore it.