Isoniazid Drug Level
Label Mnemonic: | INH |
Epic code: | LAB3451 |
Downtime form: | Doctor/Provider Orders - Pathology Core and Specialty Care Nursery |
Commercial Mailout Laboratory
6240-8 RCP
356-8593
6240-8 RCP
356-8593
Specimen(s):
Serum
Specimen
Instructions:
Indicate serum on request form and label specimen
appropriately (serum).
Collection Medium:
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Red top tube 5 mL (Clot Activator) |
Minimum:
Preferred Minimum: 2 mL serum from a red top tube
Absolute Minimum: 0.5 mL serum from a red top tube
Absolute Minimum: 0.5 mL serum from a red top tube
Rejection Criteria:
Serum gel tube
Delivery Instructions:

Testing Schedule:
Testing is performed Monday through Saturday.
Turn Around
Time:
5 days upon receipt at reference laboratory
Reference Range:
The effective concentration range of isoniazid is dependent upon the minimum inhibitory concentration of the pathogen being treated.
Toxic range: greater than 20 ug/mL
Toxic range: greater than 20 ug/mL
Methodology:
High Performance Liquid Chromatography-Tandem Mass Spectrometry (LC-
MS/MS)
CPT Code:
80375