Chronic urticaria is a disease characterized by appearance of wheals, pruritus and angioedema. In most cases, etiology and mechanism of the disease are not well understood, as is the mechanism of action of active substances used in treatment. In severe chronic urticaria cases, patients are treated with omalizumab, but not everyone responds equally to the therapy. Therefore, this study was conducted, where blood and tissue samples from 51 patients treated with omalizumab were obtained. From those samples we isolated mRNA, determined its concentration and quality, and measured the relative expression of five markers (FCER1A, CPA3, HDC, CCL3, and KIT) using RT-qPCR method. By identifying expression of markers, we tried to find changes in mast cells and basophils during the treatment of the disease, and correlate it with the different responses to the treatment. Our results show trends in support of the theory of basophil migration during the active stage of the disease. In addition, markers can be used to distinguish patients who respond to omalizumab therapy from those who don’t, which could have clinical implications as a diagnostic method to determine their response before initiation of therapy.