Glucose & Diabetes

Oral Glucose Tolerance Test (2-hour)

Normal range < 140 (normal) mg/dL (< 7.8 mmol/L SI). Specimen: Plasma (2 h post 75 g glucose).

Also known as: OGTT, glucose tolerance test.

< 140 (normal) mg/dLReference range

Reference range

This result is reported qualitatively or as a one-sided threshold rather than a two-sided numeric band.

Specimen	Plasma (2 h post 75 g glucose)
Conventional range	< 140 (normal) mg/dL
SI range	< 7.8 mmol/L
Conversion factor	×0.0555 (conventional → SI)
Panel	Glucose & Diabetes

Convert any Oral Glucose Tolerance Test (2-hour) result between units on the unit converter.

What is the normal range for Oral Glucose Tolerance Test (2-hour)?

The standard teaching reference range for Oral Glucose Tolerance Test (2-hour) is < 140 (normal) mg/dL in conventional units, or < 7.8 mmol/L in SI units. This value is measured in plasma (2 h post 75 g glucose).

Source: Adult reference values compiled from Pagana & Pagana, Mosby's Diagnostic and Laboratory Test Reference, and Fischbach & Dunning, A Manual of Laboratory and Diagnostic Tests. Reference ranges vary by laboratory, method, age, sex, and population — always use the range printed on the actual result.

Above the range

Common causes of a high Oral Glucose Tolerance Test (2-hour)

Diabetes (≥ 200 mg/dL)
Impaired glucose tolerance (140–199)
Gestational diabetes

Below the range

Common causes of a low Oral Glucose Tolerance Test (2-hour)

Reactive hypoglycemia

At the bedside

Nursing considerations

Used to screen for gestational and type 2 diabetes; keep the patient at rest during the test.

Study aid

Your notes on Oral Glucose Tolerance Test (2-hour)

Your notes

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