ABSTRACT
Methemoglobinemia (MetHb) occurs when the ferric iron with the valence of +2 contained in hemoglobin becomes +3 ferric iron due to various exogenous and endogenous reasons. MetHb shifts the oxygen dissociation curve to the left, and consequently, oxygen cannot be released into the tissues. In this paper, we present two patients who were referred to the pediatric intensive care unit due to hypoxemia after their circumcisions with local anesthesia, and who were eventually diagnosed with methemoglobinemia. There was clinical recovery without sequelae following intravenous methylene blue treatment in both patients. Prilocaine is one of the relatively frequent causes of acquired MetHb in infants and young children. Monitoring methemoglobin levels of the patients for a certain period of time using the non-invasive methods widely accessible today may prevent severe problems of this kind.