Phenytoin, Plasma - Saskatoon
Discipline
Biochemistry
Overview
Description
Ordering Recommendation
- For trough level tests, collect specimen immediately prior to the next dose
Alias
- Diphenylhydantoin
- Dilantin
Specimen Information
Specimen types accepted
- Plasma
Specimen collection container
- Preferred Collection Container: Dark Green (Lithium Heparin)
-
Alternative Collection Container: Red
Required volume
- Optimal Volume: 4.5 mL Full collection tube
- Minimum Volume: 1.0 mL
(Submitting the minimum volume makes it impossible to repeat the test or perform confirmatory/reflex testing. In some situations, a minimum volume may require a second collection)
- Capillary Volume: 400 uL
- Pediatric Volume
Transport and stability
- 4 days at 2 – 8 ºC
Rejection criteria
- Specimens received where the proper collection protocols were not followed
- Pathology and Laboratory Medicine Acceptance and Rejection Criteria
Testing Information
Relevant clinical history
Relevant Recent Medication History
- Note on requisition the dosage, date and time when medication was given
Performance
Methodology
- Kinetic Assay
Days/times performed
Availability |
|
Testing Site |
|
Maximum laboratory time
Results Reporting
- In Hospital reported within 2 hours
- Community urgent and inter-hospital reported within 4 hours
- Community routine reported within 24 hours
- Critical Results of > 120.0 umol/L with be phoned
Specimen retention time
- 3 days
Other information
Reflex Testing
- In patient requests will automatically reflex an Albumin to facilitate calculation of a Phenytoin/Albumin ratio
Last Updated: October 9, 2024