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Phenytoin (Dilantin) Level

Mnemonic:    [Phenytoin]
Name:    Phenytoin (Dilantin) Level
Specimen:    1 mL serum from a Red SST or Red top tube, or plasma from a Green PST.
Spec Stability:    Stable 5 days refrigerated.
Reference Range:    10 - 20 ug/mL
Critical Range:    > 30 ug/mL
  Method:    Enzyme Immunoassay
Note:    For suspected toxicity, collect specimen anytime. For routine monitoring, specimen should be collected prior to the next dose.