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Updated: May 28, 2026
09:43
Measurement of Heme Synthesis Levels in Mammalian Cells
Published on: July 9, 2015
Methemoglobinemia: pathogenesis, diagnosis, and management
Anna Skold1, Dominique L Cosco, Robin Klein
1Department of Internal Medicine, Emory University School of Medicine, Atlanta, GA 30303, USA.
Southern Medical Journal
|October 26, 2011
Summary
Methemoglobinemia, a condition causing cyanosis and hypoxia, can be induced by common drugs like dapsone. Diagnosis involves a saturation gap and brown blood, with methylene blue reserved for severe cases.
Area of Science:
- Clinical Medicine
- Pharmacology
Background:
- Methemoglobinemia presents with cyanosis and hypoxia.
- Common medications such as dapsone and benzocaine can induce this condition.
- Distinctive clinical signs include a saturation gap and chocolate-brown blood.
Purpose of the Study:
- To highlight the diagnostic considerations for methemoglobinemia.
- To identify common drug culprits and unique clinical features.
- To discuss treatment strategies, including methylene blue administration.
Main Methods:
- Clinical case review and literature synthesis.
- Analysis of diagnostic indicators like pulse oximetry saturation gap.
- Correlation of symptom severity with methemoglobin levels.
Main Results:
- Dapsone and benzocaine are frequently implicated in drug-induced methemoglobinemia.
- A saturation gap and characteristic blood color aid in diagnosis.
- Symptomatic presentation can occur even with low-grade methemoglobinemia in patients with impaired oxygen transport.
Conclusions:
- Methemoglobinemia diagnosis requires consideration of cyanosis, hypoxia, and specific drug exposures.
- Prompt recognition of unique clinical signs is crucial for timely diagnosis.
- Treatment decisions, including methylene blue use, should be individualized based on severity and patient comorbidities.
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