To explain an allergic basis for the development of otitis media with effusion (OME), it was suggested that the middle ear mucosa can act as an allergic "shock organ." To evaluate this possibility, 16 juvenile rhesus monkeys were passively sensitized to pollen by intravenous injection of allergic human serum. All ears were then challenged by insufflation of pollen via the nose and eustachian tube (ET), twice daily, for four to five days. Daily tympanometry and otomicroscopy were performed, and on the last day of challenge, tympanocentesis was done to recover effusions. Five animals were killed and the middle ears were processed for histologic study. The results showed that none of the ears developed a middle ear effusion or OME. It is concluded that middle ear challenge with an appropriate pollen antigen in passively sensitized rhesus monkeys does not initiate an inflammatory reaction in the middle ear or induce OME.