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Medical Term:


Pronunciation: met-he'mo-glo'bin


A transformation product of oxyhemoglobin resulting from the oxidation of the normal Fe2+ to Fe3+, a process that converts heme to hematin; because methemoglobin contains water in firm union with ferric iron, it is chemically different from oxyhemoglobin; found in sanguineous effusions and in the circulating blood after poisoning with acetanilid or potassium chlorate, among other substances.

Synonym(s): ferrihemoglobin

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