Adverse Effects of Kampo Medicines

This review summarizes the adverse effects of Kampo medicines. These adverse effects in terms of immunoallergic reactions include interstitial pneumonia, liver injury, allergic cystitis, and drug eruption. Many cases of interstitial pneumonia, liver injury, and allergic cystitis associated with Kampo formulas have been reported to be caused by formulas containing Scutellariae Radix (Scutellaria root, ogon). The known adverse effects linked to overdose of Kampo formulas include pseudoaldosteronism [caused by Glycyrrhizae Radix (licorice, kanzo)], sympathomimetic symptoms [caused by Ephedrae Herba (ephedra, mao)], aconite poisoning [caused by Aconiti Tuber (processed aconite root, bushi and uzu)], and diarrhea [caused by Rhei Rhizoma (rhubarb, daio)]. In recent years, mesenteric phlebosclerosis caused by the long-term administration of Gardeniae Fructus (gardenia fruit, sanshishi) has also been reported. It is necessary to consider these potential adverse effects when prescribing Kampo medicines in clinical practice.