A Sweat‐Patch Test for Alcohol Consumption: Evaluation in Continuous and Episodic Drinkers

Abstract

We evaluated the sweat-patch test for its ability to detect alcohol consumption. During an 8-day study, volunteers drank whisky while wearing sweat-patches that collected sweat continuously at a steady rate. We offered 1.0, 2.0, or 5.0 g etha-nol/kg/day to 6 continuous drinkers, and 5.0 g ethanol/kg/day for 2 days to 8 episodic drinkers, and removed sweat patches after 2. 4. 6, and 8 days. The concentration of ethanol in the collected sweat (C_s) rose: (1) progressively with the amount of alcohol consumed; and (2) linearly with the mean concentration of ethanol in the blood (C̄_b) jduring the sweat collection period (In C_s= 0.80 In C_b - 1.40; r = 0.93, p < 0.001). The test clearly distinguished drinkers from nondrinkers (C_s < 0.0022 G/L when no ethanol consumed; C_s > 0.0067 G/LWhen 0.5 G ethanol/kg/day consumed and when C_b > 0.013 G/L). The sweat patch test provides an objective index of drinking behavior with potential applications in clinical practice and research.