What Sugar in Urine Could Mean

Sugar in urine is often a sign of diabetes, but it can also be caused by kidney disease, pregnancy, or a side effect of medication.

Normally, there is little to no glucose (sugar) in urine. High levels of sugar in the urine, known as glycosuria, can occur when a person has high blood sugar or a kidney problem. Blood is filtered through the kidneys, which remove waste, including excess sugar. This becomes urine, which is eliminated from the body when you pee.

While sugar in urine doesn't require treatment, its underlying condition may need to be managed. Urine glucose tests can measure the amount of glucose in urine, but additional testing is needed to determine the cause.

This article explains the potential causes of glycosuria. It will also cover when to seek medical attention and how glycosuria is diagnosed and treated.

What Causes High Levels of Sugar in Urine?

High glucose levels in urine can be caused by medical conditions, a genetic mutation, certain medications, and pregnancy.

Keep in mind that some people with high sugar levels in their urine don’t show any symptoms. Even when caused by medical conditions, high sugar levels in the urine may go undiagnosed until the underlying condition progresses or is found during routine screening.

Hyperglycemia, Prediabetes, and Diabetes

Glycosuria can result from hyperglycemia, which is high blood sugar. Prediabetes, which occurs before Type 2 diabetes, as well as diabetes, which is a long-term condition marked by high blood sugar levels, can also trigger glycosuria.

Diabetes affects the hormone insulin and the body's ability to store and use sugar as energy. With uncontrolled diabetes and high blood sugar levels, the kidneys can't absorb all of the sugar. The kidneys then get rid of the excess sugar from the body through the urine.

The main symptoms of sugar in urine caused by high blood sugar include:

• Excessive thirst
• Frequent urination, especially in the middle of the night

Other signs of diabetes or high blood sugar include:

• Fatigue or low energy
• Frequent infections or slow-healing wounds
• Change in vision
• Tingling in the hands or feet
• Unexplained weight loss

Pregnancy

Because of changes in hormones and how the kidneys function during pregnancy, glycosuria may be found in about 50% of pregnant individuals. Often this isn't a cause for concern but should still be discussed with your doctor.

Gestational diabetes, or high blood sugar levels during pregnancy, can also cause glycosuria. Screening for this is an essential part of prenatal care. Symptoms may include feeling very thirsty and having to pee more than usual.

Kidney Disease

In chronic kidney disease, which is loss of kidney functioning, or after a kidney transplant, people may have high levels of sugar in their urine.

Research shows that the increased release of sugar and some essential minerals in urine is protective against the progression of chronic kidney disease in some individuals.

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

• Swelling in the feet, hands, or ankles
• Shortness of breath
• Increased need to urinate
• Difficulty sleeping
• Fatigue
• Fever

Renal Glycosuria

In some cases, glycosuria can be caused by a change in genes that are passed down through the family. This rare hereditary condition is called renal glycosuria.

This causes the kidneys to release too much glucose into the urine even when blood sugar levels are normal or low. This type of glycosuria typically doesn't have any severe symptoms.

Medications

High sugar in urine can also be a side effect of certain types of diabetes medications, known as sodium-glucose co-transporter 2 (SGLT2) inhibitors,

SGLT2 inhibitors lower blood sugar by blocking the kidneys from reabsorbing glucose. This can lead to glycosuria. Medications in this class include:

• Brenzavvy (bexagliflozin)
• Farxiga (dapagliflozin)
• Invokana (canagliflozin)
• Jardiance (empagliflozin)

Sugar in Urine: Role of Kidneys

Glucose circulates through the bloodstream and provides energy to cells. This glucose can end up in your urine.

The kidneys, small bean-shaped organs, filter blood and remove waste. The cleaned blood is transferred back to the body. The leftover waste goes to the bladder, which collects urine and is released when you pee.

While most of the sugar is reabsorbed by the kidneys and put back into the bloodstream, some may remain. This sugar travels with the rest of the fluid to the bladder, leaving the body with your urine.

Glycosuria can occur if the kidneys don't remove most of the sugar before it leaves your body as urine. It is considered glycosuria when sugar in the urine is greater than 25 mg/dL.

This often occurs from high blood sugar but can also be caused by a kidney problem.

Tests to Identify High Sugar Levels in Urine

Glycosuria is diagnosed by testing the amount of sugar in your urine. Other lab work may also be performed to look for possible underlying causes. 

Home Testing

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

If you do an at-home test, discuss the results with your healthcare provider. With conditions like diabetes or chronic kidney disease, early diagnosis is essential to help slow their progression.

Healthcare Provider Exam and Tests

To test for glycosuria, your healthcare provider may order a urine analysis to check sugar levels. They may also order blood tests to check your blood sugar levels and your kidney function.

Prediabetes and diabetes are diagnosed based on the results of:

• An A1C test, which is a blood test that examines average blood sugar levels
• A fasting plasma glucose (FPG) test, which is a blood test that requires overnight fasting and checks for diabetes
• An oral glucose tolerance test (OGTT), which requires you to ingest a special syrup drink before your blood is taken to check how well your body processes sugar
  

Results signaling prediabetes are:

• An A1C of 5.7%–6.4%
• A fasting blood sugar of 100–125 mg/dL
• An OGTT 2 hour blood sugar of 140 mg/dL–199 mg/dL

Diabetes is diagnosed at:

• An A1C equal to or greater than 6.5%
• A fasting blood sugar equal to or greater than 126 mg/dL
• An OGTT 2-hour blood sugar greater than or equal to 200 mg/dL
  

When Should You Seek Medical Attention for Sugar in Your Urine?

If you think you have sugar in your urine, reach out to your doctor so they can figure out the underlying cause.

However, there are some signs and symptoms that can indicate a severe illness that's related to blood sugar levels is happening. Diabetic emergencies require immediate medical care. If you or someone you know has the following symptoms, call 911 or go to the hospital right away:

• Changes in consciousness (how awake and alert they are)
• Passing out (fainting)
• Confusion
• Seizures
  

Complications of Sugar in Urine

High levels of sugar in urine can lead to urinary tract infections and yeast infections. In people with diabetes, frequently spilling sugar in your urine can also lead to kidney damage.

When an underlying condition causes high sugar in the urine, you may need to be monitored more frequently. Your healthcare provider will create the best treatment plan for your needs. Getting treated as soon as possible may help reduce the chance of complications if your condition progresses.

Keep in mind that some conditions can trigger serious complications. For example, conditions associated with high blood sugar levels can lead to complications like:

• Worsening eyesight or loss of vision
• Poor healing wounds
• Difficulty healing from infections
• Nerve damage in the arms and legs, which can cause weakness, pain, or difficulty with muscle control
• Kidney damage

Summary

Glycosuria is the medical term for having high levels of sugar in the urine, and it can signal an underlying health issue. Under normal conditions, urine may have trace amounts of sugar (glucose) or none at all.

High levels (above 25 mg/dL) can be caused by high blood sugar or a problem with the kidneys' filtration system. Glucose, the body's primary energy source, travels through the bloodstream, which is filtered by the kidneys. When everything works properly, the kidneys remove waste, and the sugar is reabsorbed into your blood.

In kidney disease, sugar is not recycled but passes through to urine. With high blood sugar, excess sugar is removed by the kidneys and excreted through urination. This occurs in people with prediabetes, diabetes, and pregnancy and can be a side effect of medication.

Sugar in urine can cause complications, notably yeast infections and UTIs. Chronic high sugar in urine can also lead to kidney damage. Identifying and treating the underlying cause can help prevent complications.

Glycosuria is diagnosed through urine and blood tests. Your doctor may also order other specific tests to determine the cause and appropriate treatment.