There are several chiral capillary zone electrophoretic methods for the determination of enantiomeric purity of medicinal substances in the pharmaceutical bibliography. In our studies we used four H1–antihistamines (chlorpheniramine, brompheniramine, dimethindene and cetirizine). For the enantioseparation of these compounds we applied a capillary zone electrophoretic method, using hydroxypropyl β-cyclodextrine (HP-β-CD), randommethyl β–cyclodextrine (RAMEB), sulphated β–cyclodextrine (S-β-CD) and sulphated α-cyclodextrine (S-α-CD) as chiral buffer additives. In case of chlorpheniramine, brompheniramine and dimethindene baseline separation was successful. We applied the method for the determination of enantiomeric purity of comercially available dexchlorpheniramine and dexbrompheniramine medicinal substances. For cetirizine partial separation was obtained. In case of chlorpheniramine, brompheniramine and dimethindene the effects of several experimental parameters (concentration of chiral selector and analyzed substance, buffer pH, the length of capillary and the applied voltage) were evaluated with respect to enantioseparation.