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Endoscopy 2002; 34(9): 730-734
DOI: 10.1055/s-2002-33450
Case Report

© Georg Thieme Verlag Stuttgart · New York

Methemoglobinemia Induced by Topical Benzocaine: A Warning for the Endoscopist

H.  Y.  Abdallah1 , S.  A.  Shah1
  • 1Memorial Hospital of Rhode Island, Brown Medical School, Providence, Rhode Island, USA
Further Information

Publication History

Submitted: 18 May 2001

Accepted after Revision: 17 April 2002

Publication Date:
26 August 2002 (online)

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Benzocaine is used routinely for topical pharyngeal anesthesia prior to upper endoscopy, to improve patient tolerance. A potentially fatal, although often unrecognized, complication of benzocaine use is methemoglobinemia. Here, we report a case of methemoglobinemia induced by benzocaine given before upper endoscopy. Rapid recognition of this complication and immediate treatment is essential to prevent complications related to significant tissue hypoxia. This case serves as an important reminder to physicians, especially endoscopists, about this serious side effect. Furthermore, we question the need for topical anesthesia for upper endoscopy in sedated patients.

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S. A. Shah, M.D.

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