Symptoms of Ketones in Urine

It’s normal to have a small number of ketones in your body, but when ketone levels are high, it may signal serious illness or death.

Normally, your body burns sugar for energy, but there are times—namely during times of prolonged fasting and uncontrolled diabetes—when the body may need to rely on other sources like fat for energy. When the body does not have enough sugar or can’t break it down, it turns to fat which produces substances called ketones.

These ketones are important because the brain can only use glucose and ketones as an energy source. However, when ketone levels are too high, they can become toxic to the body and may instead end up in your blood and urine. 

High levels of ketones in the urine are 1.6 to 3.0 mmol/L, and very high levels are greater than 3.0 mmol/L.

urine sample

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Frequent Symptoms

There are a number of reasons why ketone levels in the urine may be high, but symptoms of ketonuria more commonly develop in people with diabetes because they don’t make enough insulin or their body doesn’t respond well to insulin.

People with diabetes can’t use the sugar in the blood for energy, so they may need to test their urine for ketones more frequently so that they can monitor their condition and avoid developing symptoms altogether. 

Symptoms of ketonuria, or ketones in the urine, are only experienced when ketone levels are high, particularly above 0.6 mmol/L.

Symptoms of ketonuria include:

  • Frequent urination
  • Increased thirst
  • Muscle aches
  • Fatigue
  • Unexpected weight loss 
  • Shortness of breath or trouble breathing
  • Nausea, vomiting, or abdominal pain
  • Confusion
  • Fruity-smelling breath

If you have any of these symptoms and there is suspicion of diabetes or another condition that throws off your metabolic profile, a healthcare professional may suggest checking your ketones immediately.

The following conditions increase your risk of ketonuria:

  • Poorly controlled diabetes or a blood sugar level above 300 mg/dL
  • History of alcohol abuse
  • Pregnancy
  • Infection
  • Prolonged fasting
  • Ethanol ingestion

Rare Symptoms

There are three ketone bodies—acetoacetic acid, beta-hydroxybutyric acid, and acetone—which are usually insignificant in the blood and urine of individuals after eating or in the overnight-fasted state.

These ketones are important reserve energy sources, but if your diabetes is poorly controlled or you are in the midst of prolonged fasting or restrictive dieting, these trace levels can skyrocket to as high as 10 to 40 mmol/L, 70 times the normal amount of ketones that should be in the blood or urine.

High ketone levels are toxic to the body because they acidify the blood, which needs to have a tightly regulated pH level to support proper organ function. This is especially important in those with diabetes who are at risk of developing diabetic ketoacidosis, a potentially life-threatening condition.

Other rare symptoms of ketoacidosis associated with ketonuria include:

  • Cerebral edema
  • Cardiac arrest 
  • Kidney failure
  • Coma
  • Death


Even if you do not have diabetes, you can develop symptomatic ketonuria. This can happen with:

  • Chronic vomiting
  • Extreme exercise
  • Extremely low-carbohydrate diets
  • Eating disorders
  • Alcohol use disorder
  • Pregnancy

Alcoholics, extreme exercisers and dieters, and pregnant women are all at high risk of developing symptomatic ketonuria.

When to See a Healthcare Professional 

If you have diabetes and are experiencing early signs of ketonuria—like fatigue or increased thirst—you may want to contact a healthcare professional. Your provider may order a urine test to check for ketones.

In the meantime, you should increase your water intake and check your blood sugar to make sure your blood sugar levels are under control. 

Whether or not you have diabetes, if you have a fruity smell on your breath, feel confused or disoriented, or have shortness of breath, you may have high ketone levels in your blood that are putting you in danger. To prevent potentially fatal complications, seek immediate medical attention. 

A Word From Verywell

If you have diabetes, you are at higher risk of developing high levels of ketones in the urine. If you have high blood sugar levels and type 1 or type 2 diabetes, it’s important to check your ketone levels to avoid serious health complications. 

Even if you do not have diabetes, you can develop symptomatic ketonuria. This can happen with chronic vomiting, extreme exercise, low-carbohydrate diets, or eating disorders, underscoring the importance of living a healthy lifestyle and taking a holistic approach to the treatment and management of ketonuria symptoms.

Frequently Asked Questions

  • Are ketones bad?

    It depends. Ketones are a metabolic byproduct created when the body burns fat for energy. If you follow a very low carbohydrate diet, ketones in the urine show the diet is working. However, in people with diabetes, the presence of ketones often indicates a problem. Very high levels of ketones can result in a potentially fatal condition known as diabetic ketoacidosis.

  • What are the symptoms of diabetic ketoacidosis?

    Symptoms of diabetic ketoacidosis (DKA) include: 

    • Decreased alertness
    • Deep, rapid breathing
    • Dehydration
    • Dry mouth 
    • Dry skin
    • Flushed complexion
    • Frequent urination
    • Fruity-smelling breath
    • Headaches 
    • Muscle stiffness
    • Nausea and vomiting
    • Stomach pain
  • Can dehydration cause ketones in urine?

    Not typically. Ketones occur when the body burns fat for energy. Starvation can cause ketones, but dehydration does not.

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4 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. Evans K. Diabetic ketoacidosis: update on managementClinical Medicine. 2019;19(5):396-398. doi:10.7861/clinmed.2019-0284

  2. Luethi N, Cioccari L, Crisman M, Bellomo R, Eastwood GM, Mårtensson J. Prevalence of ketosis, ketonuria, and ketoacidosis during liberal glycemic control in critically ill patients with diabetes: an observational study. Crit Care. 2016 Sep 15;20:297. doi:10.1186/s13054-016-1462-7

  3. MedlinePlus. Ketones in urine.

  4. MedlinePlus. Diabetic ketoacidosis.