Desensitization (DS) protocols have empirically established their efficacy and safety in eliminating most of the hypersensitivity reactions (HSR) to drugs and other allergens. It is well established that these molecules can otherwise be lethal, for some patients, when singularly administered at therapeutic doses. These binding events and the subsequent signaling cascades have been extensively modulated by different DS methods, without any clear explanation as to why it is necessary to use increasing allergen doses. A signal processing approach is used in this Letter to introduce aliasing as the erroneous detection of higher drug doses responsible for DS procedures.