Estimated incidence per population of adverse drug reactions to Kampo medicines from the Japanese adverse drug event report database (JADER)

Abstract

ABSTRACTAimLittle information is available on the incidence per population of adverse drug reactions (ADR) to Kampo medicines. We estimated the incidence of ADRs for each Kampo medicine and examined the crude drug components of Kampo medicines that may cause ADRs.MethodsWe extracted information on ADRs caused by Kampo medicines from the Japanese Adverse Drug Event Report database (JADER) between fiscal years 2008 and 2014. The number of people who took Kampo medicines was estimated based on the production value of the Kampo formulation, the drug price, and the duration of administration.ResultsThe incidences of interstitial pneumonia and liver disorder were highest for formulations that contained Scutellaria root. However, 33% of interstitial pneumonia and 39% of liver disorder cases were reported for formulations that did not contain Scutellaria root. The majority of pseudoaldosteronism cases were caused by formulations that contained Glycyrrhiza. Mesenteric phlebosclerosis occurred most commonly in response to formulations that contained Gardenia fruit. The incidences of these ADRs varied among formulations containing these crude drugs. Odds ratio analysis indicated that additional crude drugs may have also been responsible for these ADRs. In addition, some crude drugs may prevent these ADRs.ConclusionEstimation of the incidence of ADRs caused by Kampo medicines could be a prelude to a new risk management plan, and may focus attention on formulations and crude drug components associated with previously unindicated risks.