semiatic
HI

HI on the meter (above the measuring range)

The meter measured a blood glucose higher than the top of the range it can report, so it shows HI instead of a number. It is not an error code: every manual read treats it as a very high result.

Check your meter’s manual — makers differ.

What it is for

Each manual read tells you what to do, in its own words, and the words differ. Contour (Ascensia): “Wash your hands or the test site and repeat the test with a new strip. If the meter again displays the HI screen, follow medical advice immediately.” OneTouch (LifeScan, Verio Flex): “Re-test your blood glucose level. If the result is HI again, this indicates a severe problem with your blood glucose control. Obtain and follow instructions from your healthcare professional immediately.” Accu-Chek (Roche): “If your blood glucose result is displayed as LO or HI, follow your healthcare professional’s instructions or contact your healthcare professional immediately.” FreeStyle (Abbott): with symptoms such as fatigue, thirst, excess urination or blurry vision, “follow your doctor’s recommendation to treat hyperglycaemia”; without them, the FreeStyle booklet says to retest with a new test strip first.

These pages report what each maker’s manual says and quote it wherever health is involved. They do not diagnose anything, they are not medical advice, and they never tell you how to treat a result; only your own meter’s manual and your healthcare team can do that for your model.

What it looks like
The letters HI where the number would be, sometimes flashing with an arrow. The OneTouch Verio Reflect writes the words EXTREME HIGH GLUCOSE instead.
Names makers use
HI (Accu-Chek, Contour, OneTouch Verio Flex, FreeStyle); EXTREME HIGH GLUCOSE (OneTouch Verio Reflect)

Where makes differ

The top of the range is not the same. The Accu-Chek Guide manual (Roche) says HI means “higher than 600 mg/dL”, the Contour Next One guide (Ascensia) “over 600 mg/dL”, and both OneTouch booklets (LifeScan) “over 600 mg/dL”. The FreeStyle Freedom Lite booklet (Abbott) shows HI “above 500 mg/dL (27.8 mmol/L)”, so the same blood could read as a number on one meter and HI on another. The OneTouch Verio Reflect does not print HI at all: it writes EXTREME HIGH GLUCOSE. A HI is kept in memory: the FreeStyle booklet (Abbott) says it is stored as HI and “not included in your 7-, 14- and 30-day averages”.

What it does not mean

HI is not a measurement of how high you are, only that you are above the meter’s ceiling. It is not the same as HI.t on the OneTouch Verio Flex, which LifeScan’s booklet defines as the meter being too hot to test. On FreeStyle Freedom Lite meters, Abbott lists very high glucose as one possible cause of Error 2 as well, so an error code does not rule out a very high level.

Other symbols with the same shapes

Sources

No published standard we could check defines blood glucose meter control icons, so this meaning is taken from 4 makers’ own manuals and support pages, each fetched and read on the date shown:

Written in our own words; quotations are the makers’ wording.