Evaluation of urinary concentration of Tetrahydrocannabinol (THC) and its main metabolite in urine of Cannabis users assisted in psychiatric hospital in Rio de Janeiro

Abstract

Cannabis remains the most widely consumed drug of abuse in the world. With annual prevalence of consumption between 2.6 and 5.0 %, that represents an estimated consuming population of 119 to 224 million. The reasons for determining the use of drugs of abuse is embedded in forensics, detection and monitoring of consumption in the work environment, and as a tool for health professionals in monitoring the treatment of chemically dependent people. This work presents the evaluation of the levels of the drug excreted in urine using
an analytical methodology developed for the simultaneous and fast investigation of the presence of tetrahydrocannabinol (THC) and its major metabolite, 11-nor-9-carboxy-delta-9-tetrahydrocannabinol (THC-COOH), in urine of drug users, using anion exchange resin anionic Dowex® and liquid chromatography tandem mass spectrometry (LC-MS/MS). Starting from the implementation of socio-economic survey found a pattern of multiple drugs users among those interviewed with a mean age of 38.22 years and earning up to four times the minimum wage. In 33% of patients, THC-COOH was detected above the cutoff value established by American guidelines. The results allowed to profile the user assisted in the health and evaluate urinary concentrations of the metabolite in the participating volunteers. The results allowed starting a discussion about urinary metabolite concentrations in patients on abstinence and the cutoff values practiced in this country.