Described herein are embodiments of systems and methods that utilize images of a user's face to detect alcohol intoxication. One embodiment of a system to detect alcohol intoxication includes first and second inward-facing head-mounted cameras that are located less than 5 cm from a user's face, are sensitive to wavelengths below 1050 nanometer, and are configured to capture images of respective first and second regions on the user's face. The system also includes a computer that calculates, based on baseline images captured with the cameras while the user was not intoxicated, a baseline pattern of hemoglobin concentrations at regions on the face. The computer also calculates, based on a current set of images captured with the cameras, a current pattern of hemoglobin concentrations at the regions, and detects whether the user is intoxicated based on a deviation of the current pattern from the baseline pattern.