Qian Niu Zi (Morning Glory Seeds or Pharbitis)

Chinese Herb Actions

Chinese Herb Dosage

• What is the typical dosage of Qian Niu Zi, and why is the ceiling important?

  Materia medica sources give roughly 3–9 g decocted, or a smaller 1.5–3 g when taken as powder — the powder range is lower because Qian Niu Zi’s active resin-glycoside (pharbitin) content, and therefore its purgative strength, is reduced by prolonged boiling but preserved in powdered raw or lightly processed seed. This is reference information only, not a prescription; actual dosing is a licensed practitioner’s decision.

  • Processing matters — stir-frying (a standard preparation) is used specifically to moderate the seed’s harsh purgative action while its cold nature and general effect are retained.
  • Dose ceiling — traditional and toxicological sources describe overdose (cited around >30 g in children) as the point where toxic effects — severe abdominal pain, vomiting, bloody/mucus stool, and in severe cases neurological symptoms — become likely.
  • Pediatric/elderly/weak patients — traditional sources describe markedly reduced dosing for children and caution against use in weak or deficient patients generally; this is not a substance for self-dosing at any age.

  Source: materia medica consensus on dosage ranges; Ren et al. 2020 (PMID 31883474) on processing and dose-related toxicity in an animal model. Reference only — not a prescription.

Chinese Herb Contraindications & Cautions

• Are there cautions for Qian Niu Zi?

  Qian Niu Zi is contraindicated in pregnancy and is not appropriate for weak, deficient, or elderly patients. The Sacred Lotus reference record notes: “Do not use during pregnancy. This herb has been shown to cause teratogenic (birth defects) effects.” As a harsh purgative, it is traditionally reserved for robust excess-type presentations and avoided in Spleen/Stomach deficiency, general debility, or without professional supervision.

  • Pregnancy — contraindicated; documented teratogenic potential (see above).
  • Deficiency/weak-constitution patients — traditionally avoided; the herb’s draining, purgative action is suited only to excess conditions.
  • Classical incompatibility with Ba Dou (Crotonis Fructus) — Qian Niu Zi and Ba Dou are paired as a mutual antagonism in the classical “Nineteen Mutual Fears” (十九畏) compatibility-caution list, traditionally avoided in combination. (Reference note: some historical formulas, e.g. Gan Ying Wan, do combine them, so this is a documented caution rather than an absolute rule — combination decisions belong to a qualified practitioner.)
  • Toxic classification — use should be under a qualified TCM practitioner’s supervision, at or below standard dosage, generally with appropriate processing (see Dosage).

  Source: Sacred Lotus Sacred Lotus sources & references on caution (pregnancy/teratogenicity); classical Chinese pharmacology compatibility literature (Nineteen Mutual Fears) for the Ba Dou pairing. Neutral reference disclosure, not usage instructions.

Chinese Herb Toxicity & Overdose

• Toxic. The Chinese Pharmacopoeia and much of the modern pharmacology literature classify Qian Niu Zi as toxic; the Sacred Lotus records it as “slightly toxic,” reflecting real variation across sources in how its toxicity is graded — both agree it is not a benign substance and both are kept here rather than reconciled.

  Note: “toxic” vs. “slightly toxic” gradings appear across different reference sources; we present both rather than choosing one, since the underlying toxic constituent and clinical picture are consistent regardless of grading label.

  The toxic principle is the same resin-glycoside fraction (pharbitin) responsible for the seed’s purgative action, so purgative strength and toxicity rise together. Reported overdose effects include severe gastrointestinal irritation (violent abdominal pain, vomiting, bloody/mucus diarrhea), kidney irritation (blood in the urine), and, in more severe cases, neurological symptoms such as speech impairment, dizziness, confusion, or coma. Standard processing (stir-frying) is used specifically to reduce this toxicity while keeping the intended effect (see Research).

  Source: Chinese Pharmacopoeia toxicity classification; Gao et al. 2023 review (PMID 37178984, DOI 10.1016/j.jep.2023.116634); Ren et al. 2020 processing/toxicology study (PMID 31883474). Reference note, not a safety guarantee.

• This herb is considered slightly toxic.
  (while some Chinese herbs are toxic, it must be noted that many come prepared, or are combined, to mitigate their toxicity)

Herb-Drug Interactions

• No well-established clinical herb–drug interaction studies were located for Qian Niu Zi. Given its potent cathartic/diuretic mechanism, theoretical additive effects with other laxatives, diuretics, or purgative agents are a reasonable practitioner consideration, and its documented teratogenicity means it should not be combined with, or substituted for, any treatment during pregnancy regardless of other medications. (Precautionary reasoning, not a demonstrated clinical interaction — 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 Qian Niu Zi (Semen Pharbitidis)?

  Yes — research is preclinical (cell-culture and animal studies), confirming the traditional purgative/toxic profile mechanistically; no human clinical trials were located. A 2023 review catalogs roughly 170 identified compounds (resin glycosides, terpenoids, phenolic acids, fatty acids, alkaloids) and summarizes laxative, renal, neuroprotective, insecticidal, antitumor, anti-inflammatory, and antioxidant activity reported across the preclinical literature.

  • Comprehensive review (2023) — botany, traditional use, phytochemistry, pharmacology, and toxicology of Pharbitidis Semen, summarizing decades of largely preclinical findings; concludes further mechanistic and safety work is warranted.
  • Processing and toxicology (animal model) — a controlled comparison of raw vs. stir-fried seed found the fried form retained laxative activity while showing reduced subchronic toxicity to liver, kidney, and colon tissue, supporting the traditional processing practice.
  • Mechanism of purgative action (isolated tissue) — the resin glycoside pharbitin was shown to increase tonus in isolated mouse colon (via acetylcholine-receptor signaling) while decreasing tonus in isolated ileum — a plausible mechanism for the seed’s colon-targeted purgative effect. Ex vivo tissue study, not clinical evidence.
  • Preclinical anticancer signal (cell culture) — a purified resin-glycoside fraction induced paraptosis (a non-apoptotic form of cell death) in a human colon cancer cell line via activation of the CLIC1 channel. Laboratory cell-culture finding only; not tested in animals or humans for this purpose.

  Overall, the modern evidence base is mechanistic/preclinical and consistent with traditional use as a harsh purgative and vermifuge; it does not include human efficacy trials, and none of it supports safety beyond traditional dose/processing precautions.

  Sources: PMID 37178984, DOI 10.1016/j.jep.2023.116634 (Gao et al. 2023, review); PMID 31883474 (Ren et al. 2020, processing/toxicology); PMID 35317794, PMC 8939170 (Zhou et al. 2022, mechanism); PMID 30614302 (Zhu et al. 2019, preclinical anticancer). Research context, not a therapeutic claim.

Chinese Herb Notes

• What is the difference between black (hei chou) and white (bai chou) Qian Niu Zi, and what formulas is it found in?

  Qian Niu Zi is harvested as either black seed (hei chou, from Ipomoea/Pharbitis nil) or white seed (bai chou, from Ipomoea/Pharbitis purpurea) — both are recognized sources of the same crude drug, with black seeds traditionally regarded as the stronger, faster-acting of the two.

  • Traditional distinction — black seed is traditionally considered more potent and quicker-acting; white seed is considered somewhat milder and slower.
  • Discrepancy note: at least one modern laboratory comparison found no significant difference in laxative effect between black and white seeds, which does not fully agree with the traditional potency distinction above. We keep the traditional distinction (it is widely repeated in materia medica sources) while flagging that direct experimental support is limited.
  • Formula context — in the Sacred Lotus formula database, Qian Niu Zi appears in Zhou Che Wan (a strongly water-draining formula for severe edema/ascites) and Mu Xiang Bing Lang Wan (a qi-moving formula for food stagnation and damp-heat accumulation with constipation). (Formula context, not treatment advice.)

  Source: materia medica consensus on black/white seed sourcing and traditional potency distinction; Sacred Lotus formula links (Zhou Che Wan, Mu Xiang Bing Lang Wan).

This herb antagonizes or is antagonized by:

• Ba Dou (Crotonis Fructus)

This herb is considered toxic