Interpretation of Workplace Tests for Cannabinoids

Abstract

Workplace urine drug testing for an inactive THC metabolite is common in both federally regulated and nonregulated drug testing. A positive result does not document impairment, or even recent use, when impairment is likely the most important parameter being searched for by the drug testing procedure. Most cannabinoid testing does not detect imported synthetics. Currently, urine is the most widely tested matrix, but blood, plasma, oral fluid, and hair may also be accepted in federally regulated testing in the future. This article will discuss the history, the status quo, and the possible near term future of workplace testing for marijuana in employees.

Communication between healthcare providers and medical cannabis patients regarding referral and medication substitution

“…Among patients, those using cannabis may not approach healthcare providers for fear of stigma or legal trouble. Indeed, some institutional policies prevent physicians from recommending medical cannabis (Carlini et al 2017 ), and patients may lose employment due to a positive drug screen even if they have a medical cannabis license (Kulig 2017 ). As such, many people may use cannabis without the knowledge of or input from their primary healthcare providers (PCPs) (Kruger et al 2020 ), emphasizing the lack of integration of medical cannabis into mainstream healthcare settings.…”

Is the Urine Cannabinoid Level Measured via a Commercial Point-of-Care Semiquantitative Immunoassay a Cannabis Withdrawal Syndrome Severity Predictor?

“…However, urine THC-COOH levels alone cannot be used to determine either the timeframe or the amount of the last cannabis use ( 11 , 16 , 17 ). In Germany, where inpatient detoxification of cannabis users undergoing significant levels of CWS is supported by statutory health insurance ( 3 ), the termination of the inpatient detoxification treatment phase is often empirically determined by the observation of consistent urine THC-COOH levels below a cutoff point of 50 ng/ml (the sensitivity limit of most immunoassays) ( 14 ) which corresponds to the US federally mandated immunoassay cutoff concentration ( 18 ). However, it is unclear whether levels of this biomarker—as measured by point-of-care testing (POCT)—are really associated with CWS severity in clinical practice, which influences treatment decisions regarding discharge and subsequent outpatient rehabilitation treatment for CDS ( 3 ).…”

Sensitivity, Specificity and Accuracy of a Novel EEG-Based Objective Test, the Cognalyzer®, in Detecting Cannabis Psychoactive Effects

“…Biological fluids, blood, oral fluid and urine, have been used as diagnostic matrices for detecting recent cannabis use despite known limitations. Detectable amounts of THC or metabolites are present after intoxication has subsided or through passive exposure and there are often time lags and large variability between the time cannabis was used and fluid collection [ 5 , 8 , 9 , 11 , 36 , 37 ], affecting accuracy of detection. Blood concentrations of THC have better associations with cannabis impairment [ 5 ] however decrease rapidly within minutes of cannabis inhalation [ 19 ].…”

“…Cannabinoids and metabolites are often measured in urine, blood and oral fluid to detect recent use. Drug testing is commonly done on urine samples; however, detectable levels of cannabinoids and their metabolites remain in urine the longest compared to the other two matrices [ 6 , 9 ]. In participants who do not regularly use cannabis and had not used cannabis for 3 months prior to study screening, 11-nor-9-carboxy-tetrahydrocannabinol (THC–COOH), a tetrahydrocannabinol (THC) metabolite, was present in urine 93.3 h [cut-off = 15 nanograms/millilitre (ng/ml)] after ingestion of an edible dose [ 10 ].…”