Therapeutic drug monitoring

Therapeutic drug monitoring (TDM), a clinical laboratory technology that measures drug concentrations to regulate drug dosage, has become an important treatment aid in both inpatient and ambulatory care. TDM laboratory methods, including immunoassay (EIA, FIA, and RIA) and chromatographic techniques, are used to assay blood, urine, and saliva samples of patients taking therapeutic drugs; TDM is also useful in identifying abused drugs. This assessment describes specific drug assay techniques, their respective advantages and disadvantages, and costs. TDM's contribution to treatment outcomes, its impact on existing services, implications for laboratory personnel, and the extent of the TDM marketplace are discussed. Future techniques and TDM's contribution to reducing the length of patient stays are also reviewed.