Drug screening is a common practice designed to detect specific substances in an individual’s system. These screenings often include panels for common drug classes, ensuring safety and compliance in workplaces or healthcare settings.
What is BZO on a Drug Screen?
The abbreviation “BZO” on a drug screen refers to benzodiazepines, a class of central nervous system depressant medications. These drugs, commonly known as “benzos,” include alprazolam (Xanax), clonazepam (Klonopin), diazepam (Valium), and lorazepam (Ativan). They function by enhancing gamma-aminobutyric acid (GABA), a neurotransmitter that reduces brain activity, leading to calming effects.
Why Benzodiazepines are Screened
Benzodiazepines are included in drug screens due to their medical utility and potential for misuse. These medications are prescribed for conditions like anxiety disorders, insomnia, seizures, and muscle spasms. Their sedative, hypnotic, and anticonvulsant effects make them valuable in clinical practice.
Despite therapeutic benefits, benzodiazepines carry risks, including physical dependence, addiction, and abuse. Misuse can lead to dangerous outcomes, especially when combined with other central nervous system depressants like alcohol or opioids, increasing overdose risk. Screening helps monitor adherence to prescribed regimens and identify unauthorized use, addressing public health and safety concerns.
How BZO Testing Works and Interpreting Results
BZO testing primarily involves immunoassay screens, often using urine samples, as a preliminary detection method. Immunoassays detect specific drug metabolites using antibodies, offering cost-effective and rapid results. These initial screens identify benzodiazepines or their breakdown products above a predetermined cut-off level.
A “negative” preliminary screen means the benzodiazepine concentration is below the cut-off. A “positive” result indicates the concentration exceeds this threshold. Due to potential false positives with immunoassays, any preliminary positive result requires confirmatory testing. Confirmatory tests, such as Gas Chromatography-Mass Spectrometry (GC-MS) or Liquid Chromatography-Mass Spectrometry (LC-MS/MS), are highly sensitive and specific, providing definitive identification and quantification of specific benzodiazepines and their metabolites.
Factors Influencing Test Outcomes
Several factors influence BZO drug test outcomes. The detection window, or how long benzodiazepines remain detectable, varies by drug, dosage, frequency of use, and individual metabolism. Short-acting benzodiazepines may be detectable in urine for 1-5 days, while longer-acting ones or chronic use can extend this to several weeks. Hair follicle tests offer the longest detection window, identifying use over several months.
False positive results can occur in preliminary immunoassay screens due to cross-reactivity with other substances. Medications like sertraline (Zoloft), oxaprozin (Daypro), and certain NSAIDs (e.g., naproxen, ibuprofen) have caused false positives. Some antihistamines, sleep aids containing doxylamine, and valerian root supplements can also interfere. Conversely, false negatives can arise from dilute urine, very low-dose use, or when the immunoassay lacks sensitivity for specific benzodiazepines. For accurate interpretation, individuals should disclose all prescription and over-the-counter medications they are taking.