What Is Ketonuria?

Medically Reviewed by Dan Brennan, MD on June 05, 2021

Ketonuria happens when you have high levels of ketones in your urine. It is commonly seen in people with diabetes. It can also happen during pregnancy.  

Here is what you need to know about ketonuria, along with its causes, symptoms, and treatment.

Ketones and Ketonuria

Ketones, or ketone bodies, are acidic molecules made in your liver. When the liver breaks down cells, fat, or protein to give you energy, it makes ketones as by-products. 

Your body uses these ketones to give you energy when it doesn’t have enough glucose. Normally, very small amounts of ketones are released as waste in your urine. 

If you are fasting or have health conditions like diabetes, your body makes more ketones than it can use. This increases the levels of ketone bodies in your liver. Your body tries to get rid of them when you pee, resulting in high ketone levels in urine, or ketonuria. 

High ketone levels in your body can cause an increase in acid buildup in your blood. This is called ketoacidosis, which can be harmful to your body.

Causes of Ketonuria

‌You can develop Ketonuria because of: 

Keto diet. Ketonuria is common in people who follow the keto diet. A ketogenic diet involves cutting out and limiting carbohydrates and eating fats and protein for energy. This low-calorie diet makes your body use fats and protein as fuel, which causes ketone formation and excretion.‌

Fasting. Fasting for long periods of time or the intermittent fasting diet can lead to ketonuria. During fasting, your liver starts to use up fat and protein reserves in your body to keep it going. This causes ketone formation and ketonuria. 

Diabetes mellitus. When your body has low insulin levels, your cells can’t store or use glucose for energy. This results in high blood sugar or diabetes. 

Your body is left with no option but to break down fats and proteins for energy. This results in the formation of ketone bodies as waste products. These ketones pile up in your body and can even enter your blood, causing diabetic ketoacidosis. ‌

Ketonuria is common in people with diabetes, as their body tries to eliminate excess ketones through urine.

Renal glycosuria. This is a rare health condition that makes your body release glucose through urine. It happens when the tubules in your kidney don’t function properly. 

Renal glycosuria lowers your sugar levels. This causes your liver to burn fats and protein for energy, which results in ketonuria.

Glycogen storage disease. Your body stores glucose as glycogen as an energy source. When glycogen can’t be stored properly, you can develop this metabolic disease. It forces your liver to use sources other than glycogen for energy. This causes ketones to be expelled through your urine. 

Other causes. You can also develop ketonuria due to other factors, like:‌

  • Having too much alcohol
  • Continuous exercise
  • Pregnancy
  • Starvation
  • Illness or stress
  • Hormones, such as cortisol (your stress hormone) and epinephrine (adrenaline).

‌Ketonuria can also develop in people who have heart procedures like bypass surgery. 

Symptoms of Ketonuria

‌Ketonuria often follows or causes ketoacidosis. High levels of ketones in your body can be dangerous.

Symptoms you must look for include:‌

  • Thirst and dehydration
  • Fruity smelling breath
  • Tiredness and confusion
  • Vomiting
  • Frequent peeing
  • Heavy breathing
  • High blood sugar levels

Diagnosis of Ketonuria

‌Doctors can find if you have ketonuria by checking for symptoms and through blood and urine tests.

Some commonly used tests to check for ketones include:‌

  • Blood test to check sugar levels
  • ‌Urine strip test with agents that change color when they react with ketones
  • Breath test to check for the fruity smell of acetone
  • Enzyme assays to measure ketone levels
  • Home tests using blood glucose monitoring devices

Treatment of Ketonuria

‌Ketonuria caused by fasting or diet doesn’t require treatment and will resolve on its own. But it is a serious concern when it happens due to an underlying condition. ‌

  • Ketonuria in people with diabetes is treated using insulin injections or intravenous (IV) drips. 
  • When caused by other illnesses, ketonuria can be treated using the appropriate diet, medication, or therapy for the condition. 

Prevention of Ketonuria

‌If you have diabetes, it is important to control your blood sugar levels. Closely monitor your blood glucose levels and check for symptoms to prevent ketonuria and complications that can happen because of it. 

Show Sources


‌American Diabetes Association: “DKA (Ketoacidosis) & Ketones.”
Comstock, J., Garber, A. Clinical Methods: The History, Physical, and Laboratory Examinations. 3rd edition, Butterworth Publishers, 1990.
Critical Care: “Prevalence of ketosis, ketonuria, and ketoacidosis during liberal glycemic control in critically ill patients with diabetes: an observational study.”

Encyclopaedia Britannica: "Epinephrine."
Journal of Korean Medical Science: “Ketonuria after Fasting may be Related to the Metabolic Superiority.”
National Organization for Rare Disorders (NORD): “Renal Glycosuria.”
University of Rochester Medical Center (URMC): “Ketone Bodies (Urine).”
World Journal of Gastroenterology: “Glycogen storage diseases: New perspectives.”

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