<b>Retrospective Analysis of Characteristics of Mengen</b> / 日本東洋医学雑誌

ABSTRACT

Mengen is an acute symptom that sometimes occurs after administration of a Kampo formula. It is a shortterm phenomenon and its onset indicates that the patient's clinical course will improve rapidly. It is important to distinguish it from other adverse events, which are not temporary. However, to date, detailed analysis of mengen characteristics such as its frequency, time of onset after Kampo administration, and duration have not been reported. Therefore, we report a precise analysis of mengen characteristics through a literature review of case reports published between 1945 and 2009 in Japan, and retrospective analyses of the cases in our institute.<br>The literature review revealed that 42% patients developed symptoms of mengen within a day of administration, and 79% developed symptoms within 3 days. In terms of mengen duration, the symptoms persisted for 1 day in 35% cases and 3 days in 63% cases. A diagnosis of mengen proved difficult in 39% cases that presented with atypical symptoms.<br>Overall, the retrospective analysis of the cases in our institute revealed that 11 patients (7.7%) developed mengen, among 143 patients treated with Kampo between May 2010 and November 2011.