Shu Di Huang (Chinese Foxglove Root, Steamed with Water or Alcohol, Rehmannia)

Chinese Herb Actions

Chinese Herb Dosage

• What is the typical dosage of Shu Di Huang?

  Roughly 9–30 g in decoction (commonly 10–15 g), per standard materia medica ranges and the Sacred Lotus reference content. Formula amounts in practice vary with the pattern — for example roughly 21–24 g as chief herb in Liu Wei Di Huang Wan and 9–21 g in Si Wu Tang (see combinations below).

  Preparation note: Shu Di Huang can be charred (“Shu Di Huang Tan”) to enhance its stop-bleeding quality.

  Source: Sacred Lotus reference content; Bensky & Barolet materia medica ranges; Sacred Lotus ingredient links. Reference only — not a prescription.

Chinese Herb Contraindications & Cautions

• Are there cautions for Shu Di Huang?

  Shu Di Huang is a rich, cloying herb, and its main practical caution is digestive: overuse can burden the Spleen and Stomach and lead to Qi, Blood, and/or Damp stagnation. It is traditionally not used alone in patients with weak digestion.

  • Spleen/Stomach Deficiency — the cloying nature disturbs digestion; avoid using alone with poor appetite, loose stools, or abdominal distension, and pair with Qi- or Spleen-strengthening herbs when needed.
  • Excess Damp, Phlegm, or Qi Stagnation — not appropriate for these excess patterns.
  • Pattern match — treats Blood Deficiency, not Blood Stagnation.

  Source: Sacred Lotus reference content; Bensky & Barolet / Chen & Chen materia medica cautions for the Blood-tonic category.

Chinese Herb Toxicity & Overdose

• Low. Shu Di Huang has a long history of dietary and medicinal use in TCM formulas with no significant intrinsic toxicity reported at standard decoction doses. The main real-world issue is not toxicity but digestive tolerability: its rich, cloying quality can produce gastrointestinal discomfort (e.g. bloating, loose stools) in patients with weak Spleen/Stomach function, consistent with the traditional caution above.

  Source: materia medica consensus (Bensky & Barolet / Chen & Chen). Reference note, not a safety guarantee.

Herb-Drug Interactions

• No well-established clinical herb–drug interactions are documented for Shu Di Huang as a single herb. The only directly relevant human pharmacokinetic data comes from the multi-herb formula Liu Wei Di Huang Wan (in which Shu Di Huang is chief): a 14-day study in healthy volunteers found no significant change in CYP2C19, CYP2D6, or CYP3A4 activity, suggesting a low risk of pharmacokinetic interaction with drugs metabolized by these enzymes — though this is formula-level evidence, not proof for the isolated herb. (Flagged for practitioner confirmation.)

Western / Biomedical Research

Chinese Herb Clinical Studies & Research

Provided as research context — a summary of published biomedical study, not a therapeutic or medical claim.

• Is there modern research on Shu Di Huang (Rehmanniae Radix Praeparata)?

  Yes — a growing body of animal/preclinical research supports several traditional claims (Blood tonification, Essence/Marrow nourishment, Kidney-related bone and cognitive effects), while human clinical trials on the single processed herb remain scarce. Most human data comes from formulas containing it rather than Shu Di Huang alone.

  • Blood-deficiency mouse model (2025) — comparing raw Rehmanniae Radix with the steamed/processed form (Rehmanniae Radix Praeparata, i.e. Shu Di Huang) in mice with induced Blood Deficiency Syndrome, the processed form restored hemoglobin, red-blood-cell, and platelet counts and improved bone-marrow, spleen, and vascular histology, with network pharmacology and molecular docking pointing to PI3K-AKT pathway activation. This directly supports the traditional Blood-tonifying use and the processed-vs-raw distinction; animal research, not clinical proof.
  • Alzheimer’s-model mice — Radix Rehmanniae Praeparata (Shu Di Huang) improved cognitive/spatial-memory performance and reduced tau hyperphosphorylation in a streptozotocin-induced Alzheimer’s mouse model, with effects linked to restored insulin-signaling (INSR/IRS-1/AKT/GSK-3β) and shifts in gut microbiota. Preclinical; resonates with the traditional Jing/Marrow-nourishing claim but is not evidence of a treatment for dementia.
  • Diabetic osteoporosis rat model — Rehmanniae Radix Praeparata extract (catalpol, acteoside, echinacoside) improved bone mineral density and trabecular microarchitecture in streptozotocin-diabetic rats via IGF-1/PI3K/mTOR signaling, proposed as a candidate approach for diabetic bone loss. Preclinical; connects to the traditional “fortifies Marrow” and Xiao Ke (wasting-thirsting) uses.
  • Human pharmacokinetic safety — a 14-day study of Liu Wei Di Huang Wan (chief herb Shu Di Huang) in healthy volunteers found no significant effect on CYP2C19, CYP2D6, or CYP3A4 activity (see drug interactions above); formula-level, not single-herb, evidence.

  Human clinical evidence on Shu Di Huang as an isolated herb remains limited; most support above is preclinical (cell/animal) research.

  Sources: PMID 40332770 (blood-deficiency mouse model, processed vs. raw); PMID 36843923 (Alzheimer’s-model mice, Radix Rehmanniae Praeparata); PMID 31443143 (diabetic osteoporosis rat model); PMID 22208477 (Liu Wei Di Huang Wan, human CYP450 pharmacokinetic study). Research context, not a therapeutic claim.

Chinese Herb Notes

• What is the difference between Shu Di Huang and Sheng Di Huang?

  Shu Di Huang and Sheng Di Huang come from the same plant, Rehmannia glutinosa, but processing changes their nature and use almost completely. Sheng Di Huang is the raw, dried root — cooling, it clears Heat and cools the Blood, and nourishes Yin. Shu Di Huang is the same root repeatedly wine- or water-steamed until dark and sweet — warming in comparison, it tonifies Blood and nourishes Kidney/Liver Yin and Essence, but is cloying and does not clear heat. Because the pinyin and slugs are nearly identical, confusing the two is a common and consequential error: giving Sheng Di Huang where Shu Di Huang is intended (or vice versa) can work against the intended pattern (e.g. adding a cooling, heat-clearing herb to a warming Blood/Essence-tonifying formula, or the reverse).

  • Sheng Di Huang (raw/dried) — sweet, bitter, cold; clears Heat, cools the Blood, nourishes Yin and generates fluids; used for Blood-Heat, febrile Yin damage, and thirst.
  • Shu Di Huang (wine/water-steamed) — sweet, slightly warm; nourishes Blood and Kidney/Liver Yin and Essence; cloying, and not used for Heat or Blood Stagnation patterns.

  Common combinations (Sacred Lotus formula database): Shu Di Huang is the chief Blood/Yin-nourishing herb in Liu Wei Di Huang Wan (the foundational Kidney-Yin tonic, ~21–24 g) and in Si Wu Tang (the classic Blood-tonifying formula, ~9–21 g). It also appears in Ba Zhen Tang and Shi Quan Da Bu Tang (Qi and Blood together), You Gui Wan and Zuo Gui Yin (Kidney Yang/Yin), Da Bu Yin Wan (Yin Deficiency with Heat), Di Huang Yin Zi (Kidney Yin and Yang with Essence loss), and other Blood/Essence-tonifying formulas. (Traditional formula context, not treatment advice.)

  Source: Sacred Lotus Sacred Lotus sources & references fields (Shu Di Huang vs Sheng Di Huang) and ingredient links; Bensky & Barolet / Chen & Chen materia medica for the processing distinction.