Test Code FLUC-M 
Methodology Liquid Chromatography - Tandem Mass Spectrometry (LC-MS/MS) 
Specimen Draw blood in a plain, red-top tube or serum gel tube. Spin down within two hours of draw and send 1.0 mL (minimum: 0.3 mL) of serum FROZEN in screw-capped, plastic vial.

NOTE: Serum for a peak level should be drawn 1 to 2 hours after oral dose, 30 minutes after intravenous infusion. Trough specimens should be drawn immediately prior to next scheduled dose.

Reference Values Therapeutic concentration:
Peak >25.0 mcg/mL (difficult infections may require higher concentrations)
Toxic concentration:
Peak >100.0 mcg/mL 
Analytic Time 2 Days 
Day(s) Test Set Up Monday and Wednesday 
CPT Code(s) 80299