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A ketone test
ketones in your blood or urine. Ketones are substances
that are made when the body breaks down fat for energy. Normally, your body
gets the energy it needs from
carbohydrate in your diet. But stored fat is
broken down and ketones are made if your diet does not contain enough
carbohydrate to supply the body with sugar (glucose) for energy or if your body
can't use blood sugar (glucose) properly.
Ketones can be tested in a laboratory. Or you can test for ketones anywhere you may be by using home blood or urine tests.
A blood test analyzed by a laboratory is the most accurate method
of measuring ketones. It is recommended for all people with
diabetes whenever symptoms of illness are present,
such as nausea, vomiting, or abdominal pain. These symptoms often happen with high blood sugar and may mean you have
diabetic ketoacidosis, a potentially life-threatening
Home blood or urine ketone tests:
No special preparation is needed before
having this test.
Talk to your doctor about any
concerns you have regarding the need for the test, its risks, how it will be
done, or what the results will mean. To help you understand the importance
of this test, fill out the
medical test information formmedical test information form(What is a PDF document?).
The health professional taking a sample
of your blood will:
Some home blood sugar meters can also measure blood ketones. You use the same finger-prick method that you use to measure blood sugar.
The blood sample is taken from a vein
in your arm. An elastic band is wrapped around your upper arm. It may feel
tight. You may feel nothing at all from the needle, or you may feel a quick
sting or pinch.
Your finger may feel sore after pricking it for a drop of blood for the test.
There is normally no discomfort
involved with collecting a urine sample.
There is very little risk of a problem
from having blood drawn from a vein.
There is very little risk of complications from testing your blood for ketones with a home blood sugar meter.
There are no risks associated with
collecting a urine sample.
A ketone test checks for substances made
when the body breaks down fat for energy (ketones).
There are no ketones in your blood or
Ketones are present in your blood or
Home blood sugar meters that also test for ketones display results on the meter's screen.
In people who have diabetes, blood ketones are expected to be lower than 0.6 mmol/L.
Ketones are present in the urine if:
You usually compare the color of the test strip or urine to a chart to find out if ketones are present.
You may have ketones if
The level of ketones, and not just the presence of
ketones, may be important to your doctor as well. Many conditions can change
ketone levels. Fasting usually causes only mild increases in the level. But
ketone levels in diabetic ketoacidosis are much higher. Your doctor will discuss any significant abnormal results with you in relation
to your symptoms and past health.
Reasons you may not be able to
have the test or why the results may not be helpful include:
Your doctor may recommend you test for ketones if you have
diabetes and you have any of the following conditions:
Other Works Consulted
Chernecky CC, Berger BJ (2013). Laboratory Tests and Diagnostic Procedures, 6th ed. St. Louis: Saunders.
Fischbach FT, Dunning MB III, eds. (2009).
Manual of Laboratory and Diagnostic Tests, 8th ed.
Philadelphia: Lippincott Williams and Wilkins.
August 15, 2013
E. Gregory Thompson, MD - Internal Medicine & Alan C. Dalkin, MD - Endocrinology
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