Specimen Requirements

Specimen Type: Plasma or serum

Container/Tube:

Plasma: Lithium heparin, sodium heparin, plain or gel separator, or potassium EDTA

Serum: Clot, plain, activator, or gel separator

Specimen Volume: 0.5 mL

Specimen Minimum Volume: 0.2 mL

Collection Instructions: Preferred sample time for monitoring is before the next dose (trough).