Order Code: C2354
ABN Requirement: No
Synonyms: Dilantin; Diphenylhydantoin
Specimen: Serum
Volume: 1.0 mL
Minimum Volume: 0.5 mL
Container: Red Top (no gel barrier) tube
Collection:
- Collect and label sample according to standard protocols.
- Gently invert tube 10 times immediately after draw. DO NOT SHAKE.
- Allow blood to clot 30 minutes.
- Centrifuge for 10 minutes.
- Aliquot serum into a labeled transport tube and cap tightly.
Special Instructions: Collect sample immediately prior to next dose. Record the time of the last dose of phenytoin on the requisition.
Transport: Store aliquoted serum at 2°C to 8°C after collection and ship the same day per packaging instructions provided with the Cleveland HeartLab shipping box.
Stability:
Ambient (15-25°C): 4 days
Refrigerated (2-8°C): 4 days
Frozen (-20°C): 30 days
Deep Frozen (-70°C): 30 days
Causes for Rejection: Specimens other than serum; improper labeling; samples not stored properly; samples older than stability limits; serum from gel-barrier tube/SST
Methodology: Kinetic Interaction of Microparticles in a Solution
Turn Around Time: 2 to 3 days
Reference Range:
| Age | ug/mL |
| All Ages | 10.0-20.0 |
Urgent Values:
| Age | ug/mL |
| All Ages | >40.0 |
Use: A phenytoin test is performed to monitor the concentration of the drug in the blood.
The CPT codes provided are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payer being billed.