Immunoassay-Based Drug Tests Are Inadequately Sensitive for Medication Compliance Monitoring in Patients Treated for Chronic Pain.

Background: Enzyme immunoassays (EIA) have notable limitations for monitoring therapeutic compliance in pain management. Chromatography coupled with mass spectrometry provides definitive results and superior sensitivity and specificity over traditional EIA testing.

Objective: To analyze and compare the sensitivity of EIA results together with known prescriptions to liquid chromatography-tandem mass spectrometry (LC-MS/MS) for monitoring drug use (and abuse) in patients treated for chronic pain.