Efficacy, Functions, and Contraindications of Prepared Rehmannia Root (Shu Di Huang)

Hello, Rehmannia glutinosa (prepared) is derived from the tuberous roots of *Rehmannia glutinosa* Libosch., a plant belonging to the Scrophulariaceae family. The fresh tubers undergo repeated steaming and drying processes, often with auxiliary substances such as rice wine, *Amomum villosum* (sha ren), and dried tangerine peel (*Citrus reticulata* Blanco, chen pi), until both the exterior and interior turn glossy black and the texture becomes soft and viscous. The processed material is then sliced or stir-baked over charcoal heat. This processing transforms its nature from slightly cold to slightly warm and significantly enhances its nourishing and tonifying properties. Research indicates that rehmannan—a polysaccharide found in *Rehmannia glutinosa*—exhibits notable immunosuppressive and antitumor activities. Additionally, it demonstrates pronounced cardiotonic, diuretic, hepatoprotective, hypoglycemic, anti-proliferative, anti-exudative, anti-inflammatory, antifungal, and anti-radiation effects. This herb is contraindicated in individuals with spleen- and stomach-qi deficiency. We hope the above information is helpful to you. Wishing you a happy and healthy life!