Glutinous Rehmannia (Shengdi)
Glutinous Rehmannia (Shengdi)
The Ancient Herb with Dual Potency
Glutinous Rehmannia, or Shengdi, has been a staple in Chinese herbalism for centuries. Its dual nature as both a raw and processed herb offers a diverse range of medicinal benefits. In this article, we will explore the history, processing methods, and applications of this powerful herb.
The Enigmatic Riddle and Dual Nature of Glutinous Rehmannia
Chinese folklore offers a riddle that highlights the dual nature of glutinous rehmannia. When used in its raw form, the herb is referred to as "new place." However, when processed through steaming and drying, it becomes "old place." This transformation is significant because it causes the herb to transition from a heat-reducing remedy to a treatment for blood deficiency. Thus, raw and processed forms of glutinous rehmannia are considered two entirely distinct herbs in traditional Chinese medicine.
The Art of Processing Glutinous Rehmannia
Processing raw glutinous rehmannia is an intricate process, involving ten rounds of steaming and nine rounds of sun-drying. This method gives the herb a shiny, black appearance, akin to being painted with black ink. The Chinese have refined this technique over centuries, recognizing the importance of each step in achieving the herb's full medicinal potential.
Clinical Applications and Research Findings
Modern research supports the efficacy of glutinous rehmannia in various medical applications. Studies published in the Chinese Medical Journal have demonstrated its effectiveness in treating rheumatic and rheumatoid arthritis. Additionally, combining glutinous rehmannia with licorice has been shown to be a potent treatment.
Further research in the Medical Technology Reporter reveals that processed glutinous rehmannia and licorice injections can help treat bronchial asthma. In the New Pharmacological Journal, another study indicates improvements in contagious hepatitis cases treated with raw glutinous rehmannia and licorice injections.
Herb Profile: Raw Glutinous Rehmannia
- Common name: glutinous rehmannia (raw)
- Family: berberidaceae
- Chinese name: fresh earth's yellowness
- Scientific name: Rehmannia glutinosa Libosch
- Pharmaceutical name: Radix Rehmanniae
- Part used: dried tuberous root
- Dosage: 10 to 90g
- Flavor: sweet and bitter
- Energy: cold
- Class: herbs to reduce excessive heat inside the body and herbs for lubricating dry symptoms
- Meridians: heart, liver, and kidneys
- Action: to increase yin energy to a moderate degree, bring down fire, cool down the blood, lubricate the intestine, and produce fluids
- Indications: sore throat, vomiting of blood, coughing up blood, nosebleed, discharge of urine containing blood, and diabetes
- Notes: experiments have shown shengdi to be an effective heart tonic and an effective coagulant
The rich history and multifaceted applications of glutinous rehmannia make it a fascinating and valuable herb in traditional Chinese medicine. Whether in its raw form to reduce excessive heat or processed to treat blood deficiency, glutinous rehmannia continues to be a powerful remedy in modern clinical practice. As further research unfolds, we can expect to uncover even more potential benefits of this ancient herb.