Methemoglobinemia is an uncommon but potentially serious adverse reaction to many local anesthetics and other substances. Careful review of medical and dental histories can often uncover patients who are sensitive to agents with the potential of causing methemoglobinemia. This case report is a review of the literature and demonstrates the management of methe-moglobinemia-susceptible patients.

Methemoglobinemia occurs when iron atoms in hemoglobin molecules are oxidized from their normal ferrous (Fe++) to a nonfunctional ferric (Fe+++) state, resulting in reduced oxygen delivery to the tissue level. Methe-moglobin (MetHb) is normally present in human blood at levels less than 1-2%. In normal patients, its rapid reduction back to hemoglobin is catalyzed primarily [...]