Research progress on the toxicity of Asari Radix et Rhizoma

Asari Radix et Rhizoma (ARR), also known as Xixin, has been broadly used as a traditional herbal medicine in East Asia and is an important component of classic prescriptions, including mahuang fuzi xixin decoction. It was initially classified as a “top grade” herb in ancient Chinese Pharmacopeia, Shennong’s Materia Medica. Volatile oils, lignans, fatty acids, flavonoids, and nitrogen-containing compounds are the main ARR components. Previous pharmacological studies have shown that ARR exerts beneficial effects in humans for treating headaches, toothaches, and several inflammatory diseases by dispelling wind and cold, alleviating pain, and eliminating phlegm. However, “the dosage of ARR should not exceed one coin (approximately 3.75 grams)”, as stated in Shizhen Li’s Compendium of Materia, emphasized the considerable ARR toxicity and significantly constrained its clinical application. This review aimed to consolidate recent advancements in the understanding of the toxic ARR components. Additionally, we provide an overview of the hepatotoxicity, genotoxicity, neurotoxicity, and pulmonary toxicity of ARR and discuss the underlying molecular mechanisms. This study reviews the limitations of current studies and enhances our understanding of the toxic effects of ARR from the perspective of its toxic components and mechanisms, thereby providing a theoretical basis for the rational clinical practice of ARR-based medications.