Specimen Requirements

Serum
Draw blood in a gold-top (serum separator) gel tube. Label the specimen with the patient’s name (first and last), date of birth, date and time of draw, phlebotomist’s initials, and as serum. Spin down and send 1 mL of serum refrigerated. 

Specimens drawn <6 hours after last dose are not acceptable.

Specimen stability:   8 hours at room temperature when spun
                                     2 days at 2-8°C
                                     freeze at ≥-20°C for longer storage
Minimum volume:    1 mL

*Digitoxin interferes with this assay.