Specimen Requirements

Specimen Type: Plasma or serum

Container/Tube:

Plasma: Lithium heparin (plain or gel separator), sodium heparin, potassium EDTA, sodium fluoride, potassium oxalate, or sodium citrate

Serum: Clot, plain, activator, or gel separator

Specimen Volume: 0.5 mL

Specimen Minimum Volume: 0.3 mL

Collection Instructions: Trough levels should be drawn 5 minutes before the next dose.

Note:  If testing is delayed, remove serum or plasma from the clot, red blood cells or separator gel.