Therapeutic drug management
Trough levels are most reproducible
Spin and separate within two hours of specimen collection.
Transfer vial/tube with cap - 12 mL (LabCorp)
Ambient - <3 days
Gel-barrier tubes are not recommended
High-pressure liquid chromatography with ultraviolet detection (HPLC/UV)
The effective concentration range of isoniazid is dependent on the minimum inhibitory concentration of the pathogen being treated.
Toxic range: >20 µg/mL