Acquired Methemoglobinemia Observational Registry

Inclusion Criteria

• •Adult or pediatric patients diagnosed with acquired methemoglobinemia and receiving treatment with ProvayBlue® (methylene blue 0.5%) as per the treating physician's diagnosis and the acute care facility's standard of care
• •Those acquired methemoglobinemia patients whose diagnosis is aided by measurement of methemoglobin and whose ongoing treatment is guided by re-measurement of methemoglobin \~1h post-treatment with ProvayBlue® in accordance with the US FDA Label prescribing information