Blood and Urine Ketones

Medically reviewed by Drugs.com. Last updated on May 6, 2024.

What are ketones?

Ketones are made when your body turns fat into energy. This happens when your body does not have enough insulin to turn sugar into energy. Ketones are released into your blood. Your kidneys get rid of ketones in your urine.

Why do I need to test for ketones?

High levels of blood or urine ketones can lead to diabetic ketoacidosis. Diabetic ketoacidosis is a life-threatening condition that can cause seizures, coma, or death. Early treatment of high levels of blood or urine ketones may prevent diabetic ketoacidosis.

When do I need to test for ketones?

Your healthcare provider will tell you if you need to test your urine or blood. Test for ketones when you have any of the following:

Your blood sugar level is higher than 300 mg/dl.
You have nausea, abdominal pain, or are vomiting.
You have an illness such as a cold or the flu.
You feel more tired than usual.
You are more thirsty than normal or have a dry mouth.
Your skin is flushed.
You urinate more than usual.

How do I test for urine ketones?

Ask your healthcare provider where to purchase a urine ketone test kit. The kit usually comes with a plastic cup, a bottle of test strips, and directions. Follow the instructions in the ketone test kit. Check the expiration date to make sure the kit has not expired. The following is an overview of how to test your urine for ketones:

Urinate into a clean container. You can use a clean plastic cup if your kit does not come with a cup.
Dip the test strip into the sample. The directions will tell you how long to hold the test strip in urine. Gently shake extra urine off of the strip.
You can also urinate directly onto the test strip. The directions will tell you how long to hold the test strip in your stream of urine. Gently shake extra urine off of the strip.
Wait for the test strip to change color. The directions will tell you how long you need to wait.
Hold the test strip next to the color chart on the bottle. Match the color on your strip to a color on the bottle. The color on the bottle will tell you the amount of ketones in your urine. The amount of ketones in your urine may be negative, trace, small, moderate, or large.
Write down the results.

How do I test for blood ketones?

Ask your healthcare provider where to purchase a meter that tests for blood ketones. The meter is similar to the one you use to check your blood sugar level. Your healthcare provider will teach you how to use this meter. The following is an overview on how to use a meter to test your blood for ketones:

Follow directions to set up the meter. Insert a test strip.
Clean your finger with an alcohol wipe. Let your finger dry for 30 seconds.
Use a lancet to prick your finger. Gently squeeze your finger to make it bleed.
Touch the end of test strip to the drop of blood. The meter will beep when the strip has enough blood on it.
The meter will tell you your blood ketone level on a tiny screen. Write down the results.

How are moderate or large amounts of ketones treated?

You may need insulin to decrease your blood sugar levels and stop your body from making ketones. You may need insulin as a shot or in an IV.

What else can cause ketones in my blood or urine?

A diet that is low in carbohydrates or fat
Drinking large amounts of alcohol
Certain medicines such as medicine to treat Parkinson's disease
Certain conditions such as seizure disorders or eclampsia in pregnancy

How can I prevent ketones in my blood or urine?

Keep control of your blood sugar levels to prevent your body from making ketones. Do the following to control your blood sugar levels:

Monitor your blood sugar levels as directed. Report high or low levels to your healthcare provider. You may need more insulin than usual when your blood sugar levels are high. Early treatment of high blood sugar levels may prevent your body from making ketones.
Take insulin and diabetes medicines as directed. Do not skip a dose of insulin or diabetes medicine.
Follow your meal plan. Ask your healthcare provider for more information about what you should eat. You may need to meet with a registered dietician to help you plan your meals.
Follow instructions for sick days. Your blood sugar levels may increase when you are sick. Make changes to your diabetes medicine as directed when you are sick.

Call 911 for any of the following:

You have a seizure.
You begin to breathe fast, or are short of breath.

When should I seek immediate care?

You become weak and confused.
You have fruity, sweet breath.
You have severe, new stomach pain and are vomiting.
You are more drowsy than usual.

When should I contact my healthcare provider?

Your ketone level is higher than your healthcare provider said it should be.
Your blood sugar level is lower or higher than your healthcare provider says it should be.
You have moderate or large amounts of ketones in your urine or blood.
You have a fever or chills.
You are more thirsty than usual.
You are urinating more often than usual.
You have questions or concerns about your condition or care.

Care Agreement

You have the right to help plan your care. Learn about your health condition and how it may be treated. Discuss treatment options with your healthcare providers to decide what care you want to receive. You always have the right to refuse treatment. The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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