Specimen Type/Volume

0.5 mL serum.

Shipping Information

Ship in insulated container with freezer packs.

Collection Protocol

Collect blood into a red-top vacutainer; avoid hemolysis. Allow the sample to clot. Centrifuge the sample; separate the serum from the cells and transfer to a leakproof, labelled tube. Refrigerate or freeze and ship with freezer packs. Lithium-heparin plasma is acceptable, however laboratory reference intervals are for serum samples.

Additional Information

Peak phenobarbital serum values are obtained at 4 hours post-pill. Trough serum values are obtained prior to administration of medication (pre-pill).