Application of trichloro-acetic acid (TCA) to the inferior turbinates is being performed at our hospital to treat allergic rhinitis. However, some patients have continous rhinorrhea even though the provocation test after treatment was negative. Electrophoretic studies were performed on the nasal discharge of such continuous rhinorrhea patients to analyze its protein components, albumin and 23kD protein. The results showed that the pituita in the unimproved cases with negative provocation result was similar in nature to the pituita in vasomotor rhinitis patients. It was concluded that the proteins in the pituita were not attributable to an antigen-antibody reaction, because the provocation test was negative, but they were the result of angiogenic factors (= vasomotor rhinitis). Thus it appears that allergic rhinitis can be classified into two types: genuine allergic rhinitis and allergic rhinitis associated with vasomotor rhinitis. TCA therapy was not effective in the cases of allergic rhinitis with vasomotor rhinitis, because they had a pathophysiological feature of vasomotor rhinitis. Genuine allergic rhinitis can be differentiated from vasomotor rhinitis clinically by measuring albumin and 23kD protein in pituita. It was concluded that measurement of 23kD protein concentrations in pituita is effective for determining indications for TCA chemotherapy and evaluating its clinical results.