INTRANASAL HISTAMINE, METHACHOLINE, AND BRADYKININ CHALLENGE IN CHILDREN WITH AND WITHOUT ALLERGY

In this study, allergic and non allergic children (7-13 years) were ch allenged with increasing doses (0.01, 0.1, 1.0 mg) of histamine, metha choline, and bradykinin at different study sessions. The effects of th ese challenges on nasal patency, secretion weight, sneezing, nasal sym ptoms, eustachian tube function, middle-ear pressure, and pulmonary fu nction were documented. Although intranasal challenges with the three substances provoked nasal symptoms and secretion only histamine challe nge provoked sneezing and resulted in significant changes in the measu res of nasal patency and eustachian tube function. None of the substan ces provoked changes in middle ear pressures or pulmonary function. Al lergic status had a significant effect on secretion weight and symptom s of congestion and rhinorrhea, most consistently documented as a grea ter response of the allergic subjects to histamine challenge. In gener al, the results of this study in children are similar to those previou sly described for challenges with these substances in adults.