|Specimen: ||1 mL serum from a Red top tube. Do not use GEL barrier tubes. Also acceptable EDTA or heparin tubes without gel barriers.|
Patient Prep: Timing of specimen collection: Pre-dose (trough) draw - At steady state concentration.
Centrifuge as soon as the sample is clotted. Immediately after centrifuging the sample, pipette the serum into a separate, labeled tube.