TABLE 1.

Methods that have been used for therapeutic drug monitoring (TDM)

Immunoassays	Mass spectrometry
Radioimmunoassays (RIAs)	LC–MS/MS
Enzyme‐linked immunosorbent assay (EIA)	MALDI‐MS
Enzyme‐multiplied immunoassay technique (EMIT)	GC–MS
Heterogeneous enzyme‐linked immunosorbent assay (ELISA)	Other techniques
Fluorescence polarization immunoassay (FPIA)	High‐performance liquid chromatography (HPLC)
Competitive fluorescent microsphere immunoassay (CFIA)	Atomic absorption spectrometry
Chemiluminescence immunoassay (CLIA)	Flame photometry
Immunochromatography	Electrode technique
Latex immunoagglutination inhibition method (PENTINIA)	Chromogenic technique