Fu Hai Shi (Pumice)

Chinese Herb Actions

Chinese Herb Dosage

• What is the typical dosage of Fu Hai Shi?

  Roughly 9–15 g in decoction, or 3–6 g two to three times daily as powder. Because it is a hard, porous mineral, decoction sources consistently note it should be crushed and either decocted first (before the other herbs are added) or wrapped in a cloth/tea bag during cooking, since its fragments do not settle out like a typical root or bark. When taken to help disband urinary stones it is often ground to a fine powder and taken directly rather than decocted.

  Source: cross-referenced contemporary materia medica and dispensary references (consensus dosage/preparation); reference only, not a prescription.

Chinese Herb Contraindications & Cautions

• Are there cautions for Fu Hai Shi?

  Fu Hai Shi is cold and salty, so it is traditionally avoided in cough due to Lung/Spleen deficiency-cold (thin, white, watery sputum rather than thick phlegm-heat) and used cautiously in patients with Spleen-Stomach deficiency-cold, poor appetite, or loose stools, since its cold nature can further burden weak digestion. Multiple contemporary references also list pregnancy and pediatric use as situations calling for professional supervision and dose adjustment, though it is not listed as a classically prohibited pregnancy herb.

  • Sourcing/authenticity (reference note) — genuine pumice is light enough to float on water; sinking material is traditionally regarded as a sign of substitution/adulteration. This is a quality-control note, not a safety instruction.

  Source: cross-referenced contemporary materia medica cautions; consensus summary. Use under a qualified TCM practitioner.

Chinese Herb Toxicity & Overdose

• Low. Fu Hai Shi is generally classified as a non-toxic mineral substance in materia medica references, with no significant reported toxicity at traditional doses. As with other mineral/shell substances, prolonged or excessive use is traditionally discouraged as potentially taxing to digestion (see Cautions) rather than for acute toxicity. Analytical work on natural pumice reports low trace-metal content (arsenic, cadmium, mercury, lead) consistent with pharmaceutical-grade material, though that data comes from materials-science testing rather than a toxicology study of the ingested herb.

  Source: materia medica consensus (non-toxic classification); pumice composition/trace-element data (below). Reference note, not a safety guarantee.

Herb-Drug Interactions

• No well-established clinical herb–drug interactions are documented for Fu Hai Shi. It has not been studied for pharmacokinetic or pharmacodynamic interactions with prescription medications. As with other mineral/inorganic substances taken by mouth, general caution around co-administration with oral medications (timing separation) is a reasonable, precautionary practice rather than a demonstrated 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 Fu Hai Shi (pumice)?

  Very little — Fu Hai Shi/pumice as a Chinese-medicine substance has essentially no dedicated clinical research; the modern literature that exists is historical/materials-science rather than therapeutic. This is a genuinely under-studied traditional substance, and no clinical trials of Fu Hai Shi itself were found.

  • Historical/pharmaceutical review — a geology/pharmacognosy history paper documents pumice's use as a pharmaceutical abrasive for over 2,000 years (dentifrices, wound/ulcer cleansers, eye preparations) and notes its introduction into traditional Chinese medicine by the mid-18th century as part of decoctions with other mineral substances for urinary conditions and chronic cough — consistent with, though not itself evidence for, its traditional TCM actions.
  • Materials/biocompatibility (not a TCM study) — laboratory analysis of natural pumice (from Changbaishan, China) characterized it as a porous, largely silicate mineral with low trace-metal contamination and good cytocompatibility in cell-culture testing, in the context of bone-tissue-engineering scaffold research. This documents pumice as a biomaterial; it does not investigate or support any internal/TCM therapeutic use.

  Note: The local database records Fu Hai Shi as entering only the Lung channel; several contemporary materia medica references additionally list the Kidney channel (rationalized by its use for urinary stones and its role in nodule/goiter conditions traditionally linked to Kidney theory). We could not confirm which edition of Bensky underlies the site's original entry, so our Lung-only channel assignment is left unchanged pending owner review.

  Sources: DOI 10.1144/SP375.8 (Duffin, "History of the pharmaceutical use of pumice," Geological Society, London, Special Publications 375, 2013 — historical/pharmacognosy, not a clinical study); PMID 19622010 (Li et al., pumice microstructure/composition/cytocompatibility for biomedical scaffolding, Tissue Engineering Part C, 2010 — materials science, not a TCM study). Research context, not a therapeutic claim.

Chinese Herb Notes

• How is Fu Hai Shi different from Wa Leng Zi, Hai Zao, and Kun Bu? / key combinations

  All of these are salty, mineral or sea-derived substances used to soften hardness and dissipate nodules, but Fu Hai Shi is the one most specifically indicated for Lung phlegm-heat cough — its light, porous, "floats on water" quality is traditionally read as giving it a special affinity for the Lung and for thick, stubborn sputum, distinguishing it from the other hardness-softening substances.

  • Wa Leng Zi (Cockle/Ark Shell) — also salty and softens hardness/dissipates phlegm nodules, but is a heavier shell substance more associated with dissolving masses and abdominal accumulations, and (calcined) with astringing acid reflux; less specifically a Lung-phlegm herb.
  • Hai Zao (Sargassum) and Kun Bu (Kelp) — the classic seaweed pair for goiter and scrofula, working through a different (phlegm-damp/Kidney-oriented) route; often combined with Fu Hai Shi or the shell minerals rather than substituting for it.

  Formula context: the local database links Fu Hai Shi to Ke Xue Fang ("Cough Blood Formula"), where it is combined with Qing Dai, Zhi Zi, Gua Lou Ren, and He Zi — a classic Lung-heat, phlegm-heat pattern with blood-streaked sputum. (Traditional formula context, not treatment advice.)

  Source: Bensky/Chen & Chen-consensus materia medica differentiation; Sacred Lotus formula link (Ke Xue Fang).