Pre-employment drug screening is a common practice used as a condition of employment. These tests are designed to promote workplace safety and ensure compliance with federal and organizational policies. Understanding the substances that employers typically screen for clarifies the hiring process. This article details the specific drug categories sought in standard screenings, the additions made in expanded testing, and the procedure for handling positive results from prescribed medications.
The Standard Five Substances Tested
Most pre-employment screenings use a standardized panel that checks for five categories of substances. This panel is widely adopted due to its cost-effectiveness and ability to detect the most commonly misused illicit drugs. The five categories include Cannabinoids, which detect the metabolite tetrahydrocannabinol (THC) from marijuana use.
Cocaine is identified through the presence of its primary metabolite, benzoylecgonine, indicating past use of the stimulant. The test also targets Amphetamines, a class that includes both prescription stimulants and illicit substances like methamphetamine. Certain medications prescribed for Attention-Deficit/Hyperactivity Disorder (ADHD) may fall into this category, sometimes leading to an initial positive result.
The standard panel also screens for Opiates, covering naturally derived compounds such as codeine, morphine, and the heroin metabolite 6-monoacetylmorphine. Finally, the screen looks for Phencyclidine (PCP), a dissociative anesthetic that remains on the list due to its high risk profile for safety-sensitive positions.
Expanded Panels and Specialty Screening
While the five-panel test is the industry benchmark, many employers in safety-sensitive or regulated environments opt for expanded screening tests. These broader panels, often referred to as 10-panel or 12-panel tests, incorporate additional substance categories. Expanded screens frequently include prescription depressants, such as Barbiturates and Benzodiazepines, which are commonly prescribed for anxiety or sleep disorders.
Specialty screenings also look for synthetic opioids like oxycodone and hydrocodone, which are not reliably detected by the standard opiate test. These powerful prescription pain medications, along with Methadone and Propoxyphene, are added to address the misuse of pharmaceuticals.
Some employers may further customize their panels to screen for emerging substances of concern. This can include synthetic cannabinoids, often known as “Spice” or “K2,” or synthetic cathinones, commonly called “Bath Salts”. The decision to use an expanded panel is driven by the employer’s need to mitigate specific risks associated with the job function.
Navigating Positive Results from Legal Prescriptions
A preliminary positive result on a drug screen does not automatically lead to the withdrawal of a job offer, especially when a legal prescription may be the cause. The verification process involves a Medical Review Officer (MRO), who is a licensed physician with specialized training in toxicology and drug testing regulations. The MRO acts as an impartial intermediary between the laboratory and the employer.
When the laboratory reports a non-negative result, the MRO contacts the applicant confidentially to determine if a legitimate medical explanation exists. The applicant provides proof of a valid prescription, such as for prescription opioids, ADHD medication, or benzodiazepines, which may have triggered the initial finding. The MRO confirms the validity of the prescription and verifies that the drug and dosage are consistent with the positive test result.
If the MRO confirms a legitimate medical explanation, the result reported to the employer is classified as a negative test. This ensures that the employer never receives confidential medical information about the applicant’s diagnosis or specific medications. The MRO will only report a positive result to the employer if the applicant fails to provide a legitimate medical explanation.