Comparison of urinary 5-hydroxytryptophol, breath ethanol, and self-report for detection of recent alcohol use during outpatient treatment: a study on methadone patients.

This study compared urinary 5-hydroxytryptophol (5HTOL) with breath-ethanol testing as objective ways to disclose recent drinking by outpatients attending a methadone maintenance treatment clinic. Information about quantity and frequency of alcohol use was obtained by confidential self-reports. Random screening was performed on Mondays-Fridays in connection with routine clinic visits for methadone dosing. An observed urine sample for monitoring of illicit drug use and determination of 5HTOL, expressed as a ratio to 5-hydroxyindole-3-acetic acid (5HIAA), was obtained from 202 patients (59 women and 143 men), 16 of whom refused to complete the self-report and/or do a breath-ethanol test. Patients taking disulfiram or calcium carbimide for alcohol detoxification were excluded. Among the 177 subjects remaining, 47 (26.6%) reported intake of any alcohol on the previous day (range, 10-230 g ethanol; median, 40). Only four of those could be identified by a positive breath-test, while 17 showed a urinary 5HTOL/5HIAA ratio above the cutoff limit. Their alcohol consumption (median, 60 g) was significantly higher compared with those showing ratios within the reference interval (median, 35 g). The sensitivity of 5HTOL/5HIAA testing for detecting self-reported drinking in excess of 50 g ethanol was 77%. An additional nine patients who claimed abstinence still showed abnormal 5HTOL/5HIAA ratios, and so did three of the patients who refused to do a breath-ethanol test and/or complete the self-report. Altogether, 59 of 190 methadone-maintained patients (31.1%) had been drinking any alcohol on the previous day (i.e. Sunday-Thursday) according to self-report and/or urinalysis data, 29 (49.2%) of whom were identified by the urinary 5HTOL/5HIAA ratio and only four (6.8%) by utilizing breathalyzer.