Causes and Treatments for High Levels of Sugar in Urine

Glycosuria is the presence of simple sugar, also called glucose, in your urine. It is normal to have a small amount of sugar present in your urine, but with some health conditions, the amount of sugar can reach higher than normal levels.

Glucose levels greater than 25 milligrams per deciliter (mg/dL) are considered abnormally high glycosuria. This can happen when blood sugar levels are too high or in some conditions where glucose is poorly reabsorbed into the bloodstream.

Read on to learn more about common causes, diagnosis, prognosis, and treatment options for people with glycosuria.

Why Is Sugar in Urine?

It's normal and healthy for there to be glucose in the blood, and the normal range for blood glucose is around 70 mg/dL–110 mg/dL, and it can fluctuate throughout the day. When your blood is filtered through the kidneys it carries with it the sugar that is normally in your bloodstream.

Your kidneys are then responsible for filtering blood by removing wastes and excess fluid and returning the cleaned blood back to the body, filtering the rest to the bladder to be excreted in your urine.

Most of the sugar is reabsorbed by the kidneys and put back into the bloodstream. However, some sugar remains and travels with the rest of the fluid to the bladder, leaving the body with your urine.

Glycosuria

When the amount of sugar in urine is greater than 25 mg/dL, it is considered glycosuria.

This can happen for a few different reasons including high blood sugar levels or when your kidneys are not able to reabsorb enough glucose or excrete it to keep it within a normal range.

A certain class of medications, like empagliflozin, also can remove too much glucose from the body through the urine.

Causes

Diabetes, Hyperglycemia, and Prediabetes

Glycosuria can result from the following:

• Hyperglycemia (high blood sugar)
• Prediabetes
• Diabetes

Prediabetes and diabetes are diagnosed by testing the hemoglobin A1C (Hgb A1C) to determine the average level of glucose in your bloodstream over the past three months:

• A normal Hgb A1C is below 5.7%
• Levels between 5.8% to 6.4% indicate prediabetes
• Levels greater than 6.5% indicate diabetes

Diabetes affects the hormone insulin and the body’s ability to store and use sugar as energy. With uncontrolled diabetes and elevated blood sugar levels, the kidneys aren't able to absorb all of the sugar and must excrete the excess from the body through the urine.

Kidney Disease

In some types of kidney diseases, like chronic kidney disease or after a renal transplant, people without diabetes can also have elevated levels of sugar in the urine.

Research shows that increased excretion of glucose in the urine is associated with increases in excreting electrolytes—like potassium and sodium—in urine and could be protective against the progression of chronic kidney disease.

Renal Glycosuria

In some cases, glycosuria is caused by a genetic mutation that is passed down through the family. This rare hereditary condition, called renal glycosuria, causes the kidneys to excrete too much glucose into the urine even when blood sugar levels are normal or low.

This type of glycosuria typically doesn't have any serious symptoms and is sometimes referred to as a benign condition.

Pregnancy

Because of changes in hormones and how the kidneys filter during pregnancy, glycosuria may be found in about 50% of pregnant people who have normal blood sugar levels.

Often it isn't a cause for concern for many pregnant people but should still be discussed with a doctor.

Screening for gestational diabetes is important (and a normal part of prenatal care) so that it can be controlled to prevent complications. Gestational diabetes also increases the risk of being diagnosed with type 2 diabetes in the future.

Other Symptoms

Some people with high sugar levels in their urine don’t have any additional symptoms, especially when glycosuria is genetically linked. Even when caused by diabetes or chronic kidney disease, high sugar levels in the urine are likely to go undiagnosed until the disease progresses or it is found during normal screening.

If your glycosuria is related to another disease, you could experience other symptoms.

Diabetes

If you have uncontrolled diabetes or high blood sugar levels you may experience other symptoms such as:

• Excessive thirst
• Fatigue
• Frequent infections or slow-healing wounds
• Frequent urination
• Change in vision
• Tingling and other sensations in the hands or feet
• Unexplained weight loss
• Change in alertness
• Fainting
• Difficulty focusing
• Seizures
• Erectile dysfunction

Kidney Disease

With chronic kidney disease, you may experience other symptoms such as:

• Swelling in the feet hands or ankles
• Shortness of breath
• Blood in urine
• Increased need to urinate at night
• Difficulty sleeping
• Fatigue
• Headaches

Pregnancy

It's common for glycosuria in pregnancy to have no other symptoms unless it's caused by gestational diabetes. If you have just gestational diabetes, you may experience other symptoms such as:

• Excessive thirst
• Fatigue
• Increased urination
• Weight loss
• Excessive hunger
• Increased infections

When to Seek Medical Attention

If you think you have sugar in your urine, seek medical attention to evaluate the cause and help prevent other complications from developing.

Seek immediate medical care or call 911 if you or someone you know has:

• Changes in level of consciousness
• Fainting
• Confusion
• Seizure

Diagnosis

Glycosuria, also known as glucosuria, is diagnosed by testing your urine for the amount of sugar in it. Other lab work may also be performed to look for possible causes of increased levels of glucose in your urine. 

Home Testing

A urine glucose test can be done at home by collecting a sample of your urine and using a small device known as a urine dipstick to measure glucose levels. The dipstick will change color to indicate different levels of glucose in the sample.

If you do perform an at-home test, be sure to discuss the results with your doctor and any other concerns you have. With conditions like diabetes or chronic kidney disease, early diagnosis is important to help slow the progression of these diseases and reduce complications.

Doctor Exam and Tests

To test for glycosuria, doctors will likely order a urine analysis to check sugar levels. They may also order blood tests to determine your blood sugar levels and your kidney function.

Prognosis

Your outlook with glycosuria depends on what factors may be causing it. If there are no other diseases present, symptoms or complications will be rare.

If diabetes or chronic kidney disease are contributing to the glucose in your urine, however, you will need to be monitored by your doctor since complications could develop if these diseases progress.

Uncontrolled high blood sugar levels can lead to other complications like:

• Worsening eyesight or loss of vision
• Poor healing wounds
• Difficulty healing from infections
• Nerve damage in the arms and legs
• Kidney damage

A Word From Verywell

Glycosuria may not be cause for any concern. If you do have excess amounts of sugar in your urine, it’s important to get this tested by a doctor to rule out other conditions like diabetes or chronic kidney disease.

Discuss with your doctor any treatment options that are appropriate for you and any lifestyle changes that can help to prevent complications.