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Measuring ketones and acting based on the results

Ketones can be measured from blood with a rapid meter or from the urine with a strip.

Nowadays, the ketone level is normally measured from a fingertip using a rapid meter the same way as a blood sugar self-measurements. There are dedicated meters available for ketone level measuring. Some blood glucose meters also enable checking the level of the key ketone, beta-Hydroxybutyric acid, from the blood using a dedicated strip. The normal ketone level reference limit in a blood test is 0,6 mmol/l. You will need a medical supply referral from your diabetes care provider for a ketone level meter and/or strips, just like for any medical supplies.

Ketone level can also be measured from urine. However, a urine ketone level strip only provides an indicative result; it is not as accurate as a blood test.

In the case of insulin-dependent diabetes, to prevent a ketoacidosis, you should measure the ketone level during illness, if your blood sugar level is higher than 14 mmol/l. If your general condition deteriorates or you are pregnant, you should check the ketone level when your blood sugar rises just slightly to above 12 mmol/l.

If your blood ketone level is over 3 mmol/l, contact your diabetes care provider or emergency care without a delay.

Measurement of ketones with a fingerstick blood ketone meter (mmol/l) or urine test strip

Bloodtest result mmol/l

Striptest from urine


< 0,6

No change or slight change (+)

Normal result, no special actions required

If your blood sugar is elevated, administer rapid-acting insulin according to sick day guidelines or the instructions provided by your diabetes care provider.



Slightly elevated.

If your blood sugar is above 10 mmol/l, take rapid-acting insulin as per sick day guidelines or the instructions provided by your diabetes care provider. Drink 300-500 ml of water per hour.

Check your blood sugar and blood ketones after 2 hours.



Risk of ketoacidosis is increased

Take in more fluids and rapid-acting insulin (e.g., 30-50% more) than you would take solely to correct elevated blood sugar.

If you feel unwell or your blood sugar does not decrease, contact your diabetes care provider.

> 3,0


High risk of ketoacidosis

Contact your diabetes care provider or the emergency department without delay.

Acidosis can progress to a severe level very rapidly.

Updated 30.9.2023