LABORATORY TESTING FOR RECENT ALCOHOL-CONSUMPTION - COMPARISON OF ETHANOL, METHANOL, AND 5-HYDROXYTRYPTOPHOL

The ratio of 5-hydroxytryptophol to 5-hydroxyindole-3-acetic acid (5HT OL/5HIAA) in urine was compared with concentrations of ethanol and met hanol as a way to monitor recent alcohol consumption. During detoxific ation of alcohol-dependent subjects, ethanol persisted longer in urine than in breath or plasma. Blood and urinary methanol remained increas ed for 2-6 h after blood ethanol had returned to background concentrat ions, whereas 5HTOL/5HIAA remained increased for 6-15 h. In healthy vo lunteers who had ingested alcohol (range 3-98 g) the previous afternoo n or evening, 87% (for men) and 59% (for women) of all drinking occasi ons exceeding 7 g of alcohol were identified by an increased 5HTOL/5HI AA in the first morning urine void. This compares with 32% and 12%, re spectively, identified by analysis of ethanol (>200 mu mol/ L). No gen der difference in the excretion pattern of 5HTOL/5HIAA was seen. The r esults demonstrate that 5HTOL/5HIAA provides a specific and more sensi tive method to detect recent alcohol consumption than does ethanol or methanol.