Ethyl Glucuronide and Ethyl Sulfate Assays in Clinical Trials, Interpretation, and Limitations: Results of a Dose Ranging Alcohol Challenge Study and 2 Clinical Trials

Abstract

Any drinking the night before should be detectable the following morning with EtG cutoffs of 100 or 200 ng/ml. Twenty-four hours after drinking, sensitivity is poor for light drinking, but good for heavier consumption. At 48 hours, sensitivity is low following 6 drinks or less. Increasing the cutoff to 500 ng/ml leads to substantially reduced sensitivity. Monitoring both EtG and EtS should usually be unnecessary. We recommend EtG-confirmed self-reports of abstinence for evaluation of outcomes in clinical trials.