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HelpTest ID PNYA Phenytoin, Total, Serum
Useful For
Monitoring for appropriate therapeutic concentration
Assessing compliance or toxicity
Specimen Type
Serum RedSpecimen Required
Collection Container/Tube: Red top
Submission Container/Tube: Plastic vial
Specimen Volume: 0.5 mL
Collection Instructions: Centrifuge and aliquot serum into a plastic vial within 2 hours of collection.
Specimen Stability Information
| Specimen Type | Temperature | Time |
|---|---|---|
| Serum Red | Refrigerated (preferred) | 7 days |
| Frozen | 14 days | |
| Ambient | 7 days |
Reject Due To
| Gross hemolysis | Reject |
Reference Values
Therapeutic: 10.0-20.0 mcg/mL
Critical value: ≥30.0 mcg/mL
Day(s) Performed
Monday through Sunday
Report Available
Same day/1 dayPerforming Laboratory
Mayo Clinic Laboratories in Rochester
CPT Code Information
80185
Forms
If not ordering electronically, complete, print, and send 1 of the following forms with the specimen:
-Neurology Specialty Testing Client Test Request (T732)
-Therapeutics Test Request (T831)