Toxicology

Urine Drug Screening

Urine drug screening is a crucial tool in both clinical and forensic toxicology. It is used to detect the presence of drugs or their metabolites in urine, providing valuable information for diagnosing substance abuse, monitoring patients on controlled medications, and ensuring workplace safety. Results Dx performs immunoassay Urine Drug Screening, a technique which uses antibodies to detect the presence of specific drugs or their metabolites.

Urine drug screening serves several important purposes:

Clinical Diagnosis: Assists in diagnosing substance abuse disorders and managing
patients undergoing treatment for addiction.
Medication Monitoring: Ensures compliance with prescribed medications, particularly in
chronic pain management or psychiatric care.
Workplace Safety: Prevents accidents and injuries by identifying employees under the
influence of drugs.
Forensic Analysis: Provides evidence in legal cases involving drug use or abuse.

Identifying Adulteration and Substitution

Individuals may attempt to adulterate or substitute urine samples to avoid detection. Laboratories implement measures such as temperature checks and creatinine levels to identify tampered samples. At Results Dx, we run a comprehensive specimen validity panel to evaluate key biological markers of urine specimens including pH, specific gravity, creatinine levels, and oxidant history (which identifies the presence of common over-the-counter adulterants).

Confirmation Testing

Chromatography techniques separate compounds in a mixture, allowing for the identification and quantification of drugs. Results Dx utilizes Liquid Chromatography-Mass Spectrometry (LC- MS) to perform confirmation urine drug testing. This technique uses liquid chromatography in conjunction with mass spectrometry for analyzing a wide range of substances, including those not volatile enough for GC-MS.

Testing Workflow

Initial Screening

Immunoassays are used for initial screening of the sample. Positive results indicate the presence of drugs and require confirmatory testing.

Confirmatory Testing

Positive samples from the initial screening undergo confirmatory testing using chromatography techniques, providing definitive identification and quantification of drugs.