Point of care (POC) drug testing is performed outside of the clinical laboratory in a location where the patient is receiving care.
The principle of POC drug testing devices is based on the binding of dye-conjugated antibodies to drug present in the patient's urine sample. POC immunoassay devices typical use dye-conjugated antibodies to bind specific drugs in the sample. The antibodies then laterally flow (via capillary action) and, when drug is present, are captured to a membrane using a secondary antibody. If drug is not present, the dyed detection antibodies bind the drug bound to the membrane and a colored line appears in the test window.
Despite the obvious advantage of rapid results, there are disadvantages to POC testing compared to laboratory based immunoassays. POC testing is typically performed by non-laboratory personnel and is more subjective in nature. And the tests are usually less precise than more automated and calibrated 'wet' chemistry analyzers.
Physicians should carefully evaluate the accuracy and value of POC devices before adopting them for routine use.
