Isoniazid Level
Test Code
PKINH
Description
Isoniazid (INH) is an essential first-line antibiotic used in the treatment of tuberculosis (TB). Therapeutic drug monitoring (TDM) of isoniazid is performed to ensure optimal drug levels, minimize toxicity, and prevent treatment failure or drug resistance.
Collect
Collect Serum in an 8-10 mL plain red top tube. Any other type of tube may influence accurate drug level quantification.
Patient Prep
Allow to clot for 30 minutes, separate serum from cells immediately by centrifugation and aliquot into a labeled polypropylene or similar plastic tube. Use a separate tube for each test ordered. Allow room for expansion of sample inside tube.Preferred volume: 2 mL of serum (or plasma).
Minimum volume: 1.0 mL serum (or plasma).
Pediatric Collection
If minimum volume cannot be obtained, samples can be ran with dilution calculations. 5x maximum dilution to be allowed.
Unacceptable Conditions
Thawed samples for greater than 1 hour
Storage Transport Temp
Fully complete PK requisition, Missing elements may delay resulting.
Ship samples via overnight delivery with appropriate amount of dry ice to remain frozen upon arrival.
Stability
Freeze at -70C if possible, but at minimum -20C. Up to 1 hour at room temperature.
Notes
Ship samples to be received Monday through Friday. Do not ship on Friday or Saturday.
Performed
Monday - Friday
Methodology
HPLC-UV
Turnaround Time
Within 10 business days. Weekends and holidays may delay results until following business day.
Department
Pharmacokinetics Lab
Synonyms
Pharmacokinetics (Isoniazid, Level), HPLC (Isoniazid, Level), Nydrazid (Isoniazid, Level), Mycobacteria (Isoniazid, Level), INH
Study Offerings
RUO
CAP/CLIA
Reference Interval
By Report
CPT Code
80299
New York Approved
No: Run with Waiver
FDA
LDT