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Phenobarbital Level

Mnemonic:    [PHENOBARB]
Name:    Phenobarbital Level
Specimen:    1 mL serum from a Red top tube or plasma from a Green top tube. Do NOT use gel barrier tubes.
Transport Temp:    Refrigerated
Spec Stability:    Stable up to 3 weeks refrigerated.
Ref Lab/Code:    ARUP 0090230
Reference Range:    15 - 40 ug/mL
Critical Range:    > 60 ug/mL
  Method:    Enzyme Immunoassay
Note:    For suspected toxicity, collect specimen anytime. For routine monitoring, a trough specimen should be collected prior to the next dose. If a mysoline (primidone) level is ordered also, do not order a separate phenobarbital level (it is included in the ARUP test).