The OGTT is an important tool for the diagnosis of Diabetes mellitus. Patients and clinical staff need to be aware of the potential for misdiagnosis when standard instructions regarding patient conduct before and during the test are not followed. Source of information regarding the protocol is an important aspect considering the complexity of patient preparation involved in Oral glucose tolerance test.

Keywords: Oral glucose tolerance test (OGTT), preanalytical errors in OGTT, patient preparation, OGTT protocol.

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Harini Challapalli

Department of Biochemistry,

St. John’s Medical College, Bangalore, India