Methemoglobin

Abbreviation: MetHb

Panel: Blood Gas Tests · All blood gas tests

Typical adult reference range

Conventional units<1.5 %
SI units<1.5 %

Ranges vary between laboratories and methods — compare your result with the range printed on your own report.

What a high or low result can mean

High methemoglobin: high values can be seen after exposure to certain oxidizing drugs and chemicals, and in rare inherited disorders.

These are associations, not a diagnosis: the same result can have several causes, and your clinician interprets it with the rest of your results and history.

Good to know

Measured by co-oximetry on a blood gas sample.

Please note: Reference ranges vary between laboratories, and between the methods and instruments they use — the range printed on your own report is the one your result should be compared with. A result outside the range is not by itself a diagnosis, and a result inside it does not rule out illness. These pages are an educational summary, not medical advice: always discuss your results with the clinician who ordered them, who can interpret them in the context of your health and history.