A method for detecting an analyte in a bodily fluid includes placing the detector in contact with at least one metabolite resulting from the metabolism or degradation of the analyte. The contact between the detector and the metabolite produces an optically detectable signal. The detection method includes the detection of the metabolite only in gas form, said metabolite in gas form coming from the evaporation of at least a part of said metabolite. The detection is also carried out without contact between the bodily fluid and the detector. A dressing for implementing the detection method is also described.