Coca tea consumption causes positive urine cocaine assay

Abstract

Coca tea, derived from the same plant that is used to synthesize cocaine, is commonly consumed in South America and easily obtained in the United States. To determine whether consumption of coca tea would result in a positive urine toxicology screen for cocaine metabolites. Five healthy adult volunteers consumed coca tea and underwent serial quantitative urine testing for cocaine metabolites by fluorescence polarization immunoassay. The cutoff for a positive assay was chosen at 300 ng/ml, the National Institute on Drug Abuse standard. Each participant's urine cocaine assay was positive (level exceeding 300 ng/ml) by 2 h after ingestion. Three out of five participants' samples remained positive at 36 h. Mean urine benzoylecgonine concentrations in all postconsumption samples was 1777 ng/ml (95% confidence interval: 1060-2495). Coca tea ingestion resulted in a positive urine assay for cocaine metabolite. Healthcare professionals should consider a history of coca tea ingestion when interpreting urine toxicology results.