How to Test for Ketones
Reviewed by CDE Mehandi Sharma · Updated
Ketone testing is the single most useful skill in Type 1 after treating a low. It is what distinguishes an uncomfortable high reading from the start of ketoacidosis.
There are two ways to test. Urine strips are cheaper and widely available in India — you dip them and match the colour to a chart. Blood ketone meters cost more but measure what is in your blood right now rather than what was in your urine a while ago, which makes them more useful when things are moving quickly.
When to test
- Whenever you are unwell, whatever your blood sugar is doing.
- When your blood sugar is 250 mg/dL or above.
- If you have any symptoms that could be DKA — nausea, vomiting, stomach pain, heavy breathing.
- While ill, keep re-testing every four to six hours.
What to do with the result: if ketones are present, contact your doctor. If they are more than trace amounts, or you are vomiting, that is emergency territory rather than a phone call to make tomorrow.
The practical failure here is not owning strips. They are inexpensive, they expire, and the moment you need them is not a moment for going out to buy them. Keep them at home, check the date occasionally, and take them when you travel.