Recently, basophil activation test (BAT) has been applied to the diagnosis of drug allergy. We performed BAT for various Kampo medicines taken by 12 cooperators to evaluate the concentration which arouse nonspecific reaction during incubation in BAT. When whole blood of each was incubated for 24 hours with each Kampo medicine, false positive results were frequently observed. After 1-hour incubation with Kampo medicine at high concentration (1/312.5), false positive results were sometimes observed. These results suggest that in the diagnosis of Kampo-medicine adverse reactions, BAT should be performed in the condition of 1-hour incubation with lower concentration (1/1250 or lower).

A 47-year-old woman visited our clinic, and thereafter she had taken various Kampo medicines until she turned 58 years old. She took each medicine, containing 1-3.5 g/day of glycyrrhiza, for one or two months. Hypertension or edema was not observed in those days. From the age of 60, she took 7.5 g of tokishigyakukagoshuyushokyoto, containing 2 g of glycyrrhiza, day after day. Hypertension or edema was not observed for 35 months. However, when she was 63 years old, pseudoaldosteronism with headache, hypertension, edema,and hypopotassemia was observed for the first time. This case suggests that administration period or patient's age influences the development of pseudoaldosteronism.

Incidence of glycyrrhiza-induced pseudoaldosteronism is not well understood. We examined relationships between pseudoaldosteronism incidence and daily glycyrrhiza dose in previous clinical studies. The incidence in patients administered glycyrrhiza 1 g/day was 1.0% (mean). The incidence with 2 g/day, 4 g/day and 6 g/day were 1.7% (mean), 3.3% and 11.1% (mean), respectively. Thus a dose-dependent trend toward pseudoaldosteronism incidence was suggested by previous literature.