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Common Laboratory (LAB) Values [ G ]

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Lab (Specimen)

Conventional Units

SI Units

Gastrin (serum) top of page
< 200 pg/mL (nonfasting)
< 100 pg/mL (fasting)
< 200 ng/L (nonfasting)
< 100 ng/L (fasting)
Glucagon (Serum) top of page 50 - 200 pg/mL 50 - 200 ng/L
Glucose (fasting) plasma top of page < 110 mg/dL < 6.1 mmol/L
Glucose (ADA goals) top of page
Blood sample drawn from a vein (a whole-blood sample)
Before meals (fasting) 80 mg/dL to 120 mg/dL
Bedtime: 100 mg/dL to 140 mg/dL
Blood sample drawn from a fingertip (plasma blood sample)
Before meals (fasting) 90 mg/dL to 130 mg/dL
Bedtime: 110 mg/dL to 150 mg/dL
Less than 180 mg/dL one to two hours after meals.

The ADA also recommends a hemoglobin A1c (HbA1c) target level of less than 7%.
Glucose-6-phosphate dehyrogenase (G6PD) (Blood) top of page 5 - 13 U/g Hb 5 - 13 U/g Hb
Glucose tolerance test (GTT) Plasma top of page
Fasting Blood Glucose
From 70 to 99 mg/dL (3.9 to 5.5 mmol/L) Normal glucose tolerance
From 100 to 125 mg/dL (5.6 to 6.9 mmol/L) Impaired fasting glucose (pre-diabetes)
> /= 126 mg/dL (7.0 mmol/L)  on more than one testing occasion Diabetes

Oral Glucose Tolerance Test (OGTT)
[except pregnancy]

(2 hours after a 75-gram glucose drink)
Less than 140 mg/dL (7.8 mmol/L) Normal glucose tolerance
From 140 to 200 mg/dL (7.8 to 11.1 mmol/L) Impaired glucose tolerance (pre-diabetes)
Over 200 mg/dL (11.1 mmol/L) on more than one testing occasion Diabetes

Gestational Diabetes Screening: Glucose Challenge Test
(1 hour after a 50-gram glucose drink)
Less than 140* mg/dL (7.8 mmol/L) Normal glucose tolerance
140* mg/dL (7.8 mmol/L) and over Abnormal, needs OGTT (see below)
* Some use a cutoff of >130 mg/dL (7.2 mmol/L) because that identifies 90% of women with gestational diabetes, compared to 80% identified using the threshold of >140 mg/dL (7.8 mmol/L).


Gestational Diabetes Diagnostic: OGTT
(100-gram glucose drink)
Fasting* 95 mg/dL (5.3 mmol/L)
1 hour after glucose load* 180 mg/dL (10.0 mmol/L)
2 hours after glucose load* 155 mg/dL (8.6 mmol/L)
3 hours after glucose load* ** 140 mg/dL (7.8 mmol/L)
* If two or more values are above the criteria, gestational diabetes is diagnosed.
** A 75-gram glucose load may be used, although this method is not as well validated as the 100-gram OGTT; the 3-hour sample is not drawn if 75 grams is used.
Gamma Glutamyl Transferase, Serum  (GTT) top of page Male:  8-61 U/L (< 65 U/L)
Female 5-36 U/L (< 45 U/L)
 
Growth Hormone (serum) GH top of page < 8 ng/mL < 8 µg/L

Important Notes  top of page icon

>Unless noted, all values are for adults.
>All laboratory values listed are method dependent (Methods include: immunoassay, colorimetry, electrophoresis, HPLC, etc).
>Values may vary between laboratories.
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Medical Calculators - A thru Z
Lab Values - A thru Z