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Item Value
Approval req'd? No
Available Stat? No
Test code MEXL
Performed by Quest
Sendout? Yes
Method Gas chromatography
Container type Red top (Gold top NOT acceptable)
Amount to Collect 4 mL blood
Sample type Serum
Preferred volume 2 mL serum
Min. Volume 1 mL serum
UCSF Rejection Criteria Collected in Gold top
Processing notes Refrigerate serum. Order Quest # 4934Z.
Units µg/mL (mcg/mL)
Normal range
Therapeutic 0.5-2.0 µg/mL
Toxic ≥ 1.5 µg/mL
Critical value Quest Priority-1: ≥ 5 µg/mL
Quest Priority-2: 2.0-4.9 µg/mL
Turn around times Test performed Monday, Wednesday, Friday. Turnaround time: 2-5 days.
CPT coding 80299-90
LOINC code 3819-0
Last Updated 6/21/2016 12:14:57
Entry Number 661
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