Histamine in nasal secretions.

The histamine content of secretions collected by small-volume nasal washes was assayed by a spectrophotofluorometric method. A wide range of histamine concentrations (less than 5-1,519 ng/ml) was found. The mean concentration in secretions from normal individuals (91 ng/ml) was not significantly different from that found in allergic individuals (51 ng/ml). Females had significantly lower concentrations than did males. Sequential sampling in normals and allergics showed a great deal of daily variation in histamine content. This technically simple method may prove useful in examining the epidemiology and pathophysiology of allergic rhinitis.