Apparently, there exists a pool of histamine in the human nose that can be transferred to lavage fluid during glandular hypersecretion. The source of this histamine is yet to be identified. As the level of histamine seems to be affected by the secretory activity of nasal glands, we question the use of this single mediator as an index of mast cell/basophil activation in nasal lavage studies.

Major abdominal surgery induces an increase of serum IgE. This increase can be prevented by preoperative treatment with prednisolone, but not with ranitidine.