⛩️Kampo / Japanese Medicine

Polygonum (Kashuu)

Polygonum multiflorum

About Polygonum (Kashuu)

Polygonum (Kashuu) (Polygonum multiflorum) is a herb used in the Kampo / Japanese Medicine tradition to help with Hair Loss, Cholesterol, Insomnia, and Aging. The aerial parts and leaves are the parts traditionally used, taken internally.

Botanical background

Reynoutria multiflora (synonyms Fallopia multiflora and Polygonum multiflorum) is a species of flowering plant in the buckwheat family Polygonaceae. It is known as tuber fleeceflower and Chinese knotweed. It is native to central and southern China.

Source: Wikipedia, via iNaturalist

Parts used

Aerial Parts · internalLeaves · internal
🍵

Tea / Infusion

1–3 cups daily
  • Steep 1–2 tsp of dried Polygonum (Kashuu) in freshly boiled water for 5–10 minutes.
  • Cover while steeping.
  • Strain and drink.
💧

Tincture

20–40 drops in water, 2–3× daily
  • Pack dried Polygonum (Kashuu) into a jar and cover with 40–60% alcohol.
  • Seal and steep for 4–6 weeks, shaking daily.
  • Strain and store in a dark dropper bottle.
💊

Powder / Capsule

500 mg – 1 g, 1–3× daily
  • Grind dried Polygonum (Kashuu) into a fine powder.
  • Fill size 00 capsules or stir into smoothies or honey.
🛁

Herbal Bath

2–3× per week as needed
  • Brew 4–6 tbsp of Polygonum (Kashuu) in 1 litre of hot water for 15 minutes, strain, and add to a warm bath.
  • Soak for 20–30 minutes.

Pregnancy, Breastfeeding & Children

No herb-specific pregnancy/child safety research is documented for Polygonum (Kashuu) in our references — the guidance below is based on its general effect category, not research on Polygonum (Kashuu) itself. Always confirm with a midwife, doctor, or pediatrician.

Pregnancy

Use Caution

This herb has blood-thinning (antiplatelet/anticoagulant) activity. These are generally used cautiously in pregnancy and are typically discontinued in the weeks before delivery due to bleeding risk — this is a general, mechanism-based caution, not herb-specific research.

Breastfeeding

Likely Safe

Blood-thinning herbs are generally considered lower-risk during breastfeeding than in late pregnancy, though caution is still reasonable, especially at concentrated doses.

Children

Use Caution

Blood-thinning herbs are generally used cautiously in children, particularly around any planned surgery or dental work.

Contraindications

  • Pre-surgery — discontinue at least 2 weeks prior (potential antiplatelet effect)
  • CNS medications (benzodiazepines, SSRIs, MAOIs) — may potentiate sedative or serotonergic effects

Warnings

⛔ Heart & Blood Pressure Medications

May interact with antihypertensive drugs, blood thinners, or cardiac medications. Do not combine without medical guidance.

⚠️ Sedatives & Antidepressants

May potentiate the effects of sedative, anxiolytic, or antidepressant medications. Use with caution alongside any CNS-active drugs.

⚠️ Allergic Reactions

Discontinue immediately if you experience rash, itching, swelling, or difficulty breathing.

⚠️ Not Medical Advice

This information is for educational purposes only. Always consult a qualified healthcare provider before using herbal remedies.

Drug & herb interactions

May thin the blood

Watch for: Anticoagulants (warfarin), antiplatelets (aspirin, clopidogrel), and other blood-thinning herbs or supplements (ginkgo, garlic, fish oil, vitamin E)

Combining blood-thinning substances can increase bleeding risk, including before surgery or dental work.

May have a calming/sedative effect

Watch for: Benzodiazepines, sleep medications, other sedative herbs, and alcohol

Combined CNS-depressant effects can cause excessive drowsiness or impaired coordination.

Where to find in nature

Native region

Japan, China, Korea

Climate

Temperate to subtropical

Habitat

Mountain forests and cultivated herb farms across Japan and East Asia

🌿 To see Polygonum (Kashuu) growing, visit botanical gardens, university plant collections, or specialist herb nurseries near you. If foraging in the wild, always work with an expert identifier — never consume a plant you are not 100% certain of.

Where to buy

In store

  • Health food stores (Whole Foods, Natural Grocers, Holland & Barrett, GNC)
  • Naturopathic clinics and integrative medicine practices
  • Specialist herbal apothecaries and herbalist practices
  • Farmers markets with herb vendors

Online

iHerb

Wide selection of standardised extracts, capsules, and powders with lab testing

Mountain Rose Herbs

Premium bulk dried herbs — certified organic, ethically sourced

Starwest Botanicals

Large selection of certified organic bulk herbs and powders

Herb Pharm

High-quality liquid extracts and tinctures, rigorous quality standards

Amazon

Convenient — verify brand certifications and check third-party testing

Etsy

Small-batch artisan herbalists, hand-harvested and wildcrafted herbs

Quality tips

When buying Polygonum (Kashuu), look for: certified organic labelling, clearly stated country of origin, third-party lab testing for heavy metals and pesticides, and a batch expiry date. Standardised extracts offer consistent dosing; bulk dried herbs are more economical for regular use. Avoid very cheap, unlabelled products — quality varies enormously.