What to Do If You Notice a Sudden Onset of Sweet-Smelling Urine

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Sweet-smelling urine can be caused by a number of medical conditions, some of which can be serious and require immediate attention from a healthcare professional.

The sweet smell itself comes from chemicals or by-products made in the pee from certain bacteria, glucose, or amino acids. The presence of these chemicals is not normal, especially when onset is sudden.

Some conditions that cause this sweet smell to your urine can be life-threatening and warrant an immediate visit to your healthcare provider.

Closeup of hand holding urine sample

Science Photo Library / Getty Images

Causes of Sweet-Smelling Urine

Though changes in the smell, color, and appearance of urine have a wide variety of causes from benign to life-threatening, sweet-smelling urine specifically suggests the presence of a medical condition.

The following are some of the most common causes, but anyone with a sudden onset of sweet-smelling urine should speak with a healthcare professional immediately to pinpoint the exact cause.

Hyperglycemia and Diabetes

Hyperglycemia (high blood glucose) is common in people with undiagnosed or poorly controlled diabetes. High glucose in the urine can give urine a sweet or fruity cereal smell.

This change in smell in the urine is a sign that the glucose in your blood is too high.

The First Sign of Diabetes

For some, fruity smelling urine is the first sign that they have developed diabetes.

Sweet-smelling urine from diabetes is often accompanied by other signs of diabetes which include:

  • Excessive thirst
  • Increased need to drink water
  • Frequent urination

Diabetic Ketoacidosis (DKA)

DKA is a very serious, even life-threatening, condition in which ketones build up in the blood, making it too acidic.

In people with diabetes, body cells have difficulty receiving the glucose they need for energy, due to lack of insulin, insulin resistance, or lack of glucose (hypoglycemia) sometimes due to too much insulin from insulin injections or diabetes medications.

When the cells can’t access glucose, they begin to break down fat for energy. The resulting chemicals are called ketones.

When ketones build up in the body, they can poison the body. This is called DKA and is very serious.

DKA can happen to people with both type 1 and type 2 diabetes. It is more common when the diabetes is not yet diagnosed or uncontrolled.

DKA can come on slowly, or it can happen quickly, even within hours, particularly if nausea or vomiting are present.

Early signs of DKA include:

  • Thirst
  • Very dry mouth
  • High blood sugar levels
  • High ketone levels in the urine

Symptoms that appear after the early symptoms include:

  • Nausea, vomiting, or abdominal pain
  • Constantly feeling tired
  • Dry or flushed skin
  • Breath that has a fruity odor
  • Difficulty breathing
  • Difficulty paying attention
  • Confusion

If DKA goes untreated, it can result in coma or death. It is considered a medical emergency, and medical attention is needed at the first signs of DKA or impending DKA. This can include going to the nearest emergency room.

Urinary Tract Infections (UTIs)

Urinary tract infections (UTIs) are the result of bacteria such as E. coli entering the urinary tract (kidneys, ureters, bladder, and urethra).

UTIs are common, resulting in 8 to 10 million visits to healthcare providers each year. UTIs are more common in females due to a shorter urethral length and post-menopausal changes inside the vagina.

UTIs can make urine foul-smelling, but it can also cause sweet-smelling urine.

Other symptoms of UTIs include:

  • Frequent and urgent need to urinate
  • Pain when urinating
  • Nighttime urination
  • Urine leakage
  • Blood in urine
  • Changes in the odor of urine, especially foul-smelling
  • Cloudy urine
  • Pain in the side, abdomen, lower back, penis, or pelvic area
  • Pressure in the lower pelvis
  • Pain during sex
  • Temperature over 100 F and chills
  • Fatigue
  • Vomiting
  • Mental changes or confusion

Foetor Hepaticus

Foetor (sometimes spelled fetor) hepaticus primarily refers to odious breath resulting from liver disease, but can also affect the urine.

Also known as “breath of the dead,” foetor hepaticus is caused by volatile compounds, produced as a result of liver damage, entering the lungs.

Maple Syrup Urine Disease

Maple syrup urine disease (also called branched chain ketoaciduria) is an inherited disorder in which a newborn baby is unable to process amino acids properly.

The most common and most severe form of maple syrup urine disease is the classic type, which is usually noticed shortly after birth. Other forms of the disease can show up in later infancy and childhood, and though less severe, still require medical attention.

Maple syrup urine disease occurs in one in 185,000 infants worldwide.

Symptoms of maple syrup urine disease include:

  • Sweet-smelling urine
  • Poor feeding
  • Vomiting
  • Lethargy (lack of energy)
  • Abnormal movements
  • Delayed development

If maple syrup urine disease is left untreated, it can lead to seizures, coma, and death.

An Important Symptom

No matter what is causing sweet-smelling urine, this symptom by itself is enough reason to contact a medical professional immediately, even if it is the only symptom.


Sweet-smelling urine necessitates consultation with a healthcare provider, regardless of the cause or additional symptoms. The healthcare provider is likely to do a urinalysis (urine test) no matter which condition is suspected.

Depending on the other symptoms present, the healthcare provider may run additional tests such as:

  • Blood tests
  • Imaging
  • Genetic analysis


Sweet-smelling urine is managed by treating the underlying condition.


Treatment for diabetes depends on the type of diabetes, but usually involves lifestyle changes such as a healthy diet and exercise.

In most cases, people with type 1 diabetes will require insulin through injection or pump.

People with type 2 diabetes or gestational diabetes can sometimes manage the condition through lifestyle changes alone, but can require insulin or medications to keep their diabetes under control.

Diabetic Ketoacidosis (DKA)

As DKA is a medical emergency, it is usually treated in a hospital setting with insulin, fluids, and more.

Urinary Tract Infections (UTIs)

UTIs are treated with antibiotics decided upon by which type of bacteria is causing the infection. While they won’t cure the UTI, there are medications that can help ease symptoms during treatment.

Foeter Hepaticus

Treatment for foeter hepaticus involves treating the damaged liver, and if applicable, what is causing the liver damage.

Treatment will be individualized, but can involve medications and liver-friendly lifestyle changes such as a healthy diet and eliminating alcohol.

Liver damage cannot always be reversed.

Maple Syrup Urine Disease

Maple syrup urine disease cannot be cured and requires lifelong treatment. It is managed through a carefully maintained protein-restricted diet and with the use of supplements.

Metabolic crises that can result from this condition require immediate medical attention.

Preventing Sweet-Smelling Urine

Preventing sweet-smelling urine involves preventing the underlying cause.


Type 1 diabetes is an autoimmune disorder that cannot be prevented; most people who are affected are born with this condition.

Type 2 diabetes occurs at a later age. Symptoms and side effects from type 2 diabetes can be prevented through healthy lifestyle choices.

To prevent the sweet-smelling urine associated with diabetes, blood sugar levels need to be controlled and the diabetes managed.

Diabetic Ketoacidosis (DKA)

Managing diabetes is the first step in preventing DKA. Recognizing and addressing early warning signs is also important.

Ketone levels can be checked and monitored at home using test strips. This is especially important to do during illness (such as a cold or flu). If ketone levels are high, a healthcare provider should be contacted, particularly if blood sugar is also high and/or vomiting is present.

Avoid exercising if ketones and blood sugar levels are high. This could indicate that your diabetes is out of control and warrants a consultation with a healthcare provider.

Urinary Tract Infections (UTIs)

There are several ways to help prevent contracting a UTI:

  • Drink plenty of fluids, particularly water, to help flush bacteria from the urinary tract.
  • Practice good hygiene, such as wiping from front to back, hand-washing, and changing menstrual products frequently.
  • Avoid fluids and foods such as alcohol, citrus juices, caffeinated drinks, and spicy foods, which can irritate the bladder.
  • Urinate before and after sex.
  • Wash the genital area with warm water before sex. Do not douche.
  • Avoid genital deodorants.
  • Change birth control methods if necessary (diaphragms and/or spermicide can increase the risk of UTIs).
  • Use water-based lubricant during sex.
  • Wear cotton underwear and avoid tight clothing.
  • Consider cranberry supplementation.

People who get frequent UTIs may be put on low-dose antibiotics to prevent infection.

Foeter Hepaticus

Taking care of your liver is the best way to prevent foeter hepaticus.

Practicing the following can help prevent liver disease:

  • Exercise regularly.
  • Maintain a healthy weight.
  • Avoid alcohol or other liver toxins.
  • Take medications only as necessary; review in detail side effects and interactivity with your other medications or supplements.
  • Keep up-to-date with vaccinations.
  • Practice safety while traveling with regard to food, drink, and local health threats.
  • Ensure proper guidelines are followed during body modification procedures such as tattoos and piercings.
  • Practice safe sex for STI prevention.

Maple Syrup Urine Disease

Maple syrup urine disease is a recessive genetic disorder, meaning a person needs to receive an affected gene from both parents in order to develop the condition.

If both parents are carriers of the disease (meaning they have one affected gene and one unaffected gene), their chances (with each pregnancy) of having a child with the condition is 25%. The chances of their child being a carrier is 50%, and the chances of their child not receiving an affected gene at all is 25%.

Genetic testing can be performed on the parents before conception and/or on the zygote/embryo/fetus after conception.

A Word From Verywell

Sweet-smelling urine can be caused by a number of different conditions, some of which can be serious or life-threatening.

If you notice a change in the odor of your urine, including a sudden onset of sweet-smelling urine, seek prompt or immediate medical attention.

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10 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. The Diabetes Council. Your urine and diabetes: what you should know.

  2. American Diabetes Association. DKA (ketoacidosis) & ketones.

  3. Cleveland Clinic. Urinary tract infections: causes, symptoms & treatment.

  4. Vandenvelde S, Nevens F, Vanhee P, Vansteenberghe D, Quirynen M. GC–MS analysis of breath odor compounds in liver patientsJournal of Chromatography B. 2008;875(2):344-348. doi:10.1016/j.jchromb.2008.08.031

  5. MedlinePlus. Maple syrup urine disease.

  6. National Institute of Diabetes and Digestive and Kidney Diseases. Insulin, medicines, & other diabetes treatments.

  7. MedlinePlus. Diabetic ketoacidosis.

  8. National Organization For Rare Disorders. Maple syrup urine disease.

  9. American Urological Association. Recurrent uncomplicated urinary tract infections in women.

  10. Stanford Healthcare. Liver disease prevention.