IGHE and allergic rhinitis: The aims of the present study are to develop an allergic rhinitis model in rats in accordance with the literature, to divide the rats with allergic rhinitis into groups and administer oleuropein or standard therapy to each group, to take tissue samples and compare them histopathologically and immunohistochemically, as well as to compare the levels of immunoglobulin E (IgE) and ovalbumin-specific IgE in the blood of the rats.