Described herein are systems, methods, and computer programs for detecting an allergic reaction. In one embodiment, a system configured to detect an allergic reaction of a user, includes: a frame configured to be worn on the user's head； a thermal camera, weighing less than 5 g, physically coupled to the frame, located less than 10 cm away from the user's face, and configured to take thermal measurements of at least part of the user's nose (THN)； and a circuit configured to determine an extent of the allergic reaction based on THN.
