Chinese Knotweed Ingredients & Drug Interactions
by Hawaii Pharm
What is this page for?
First and foremost: checking Chinese Knotweed against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.
Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy
Chinese Knotweed is a dietary supplement by Hawaii Pharm with 1 active ingredient. Its ingredients are commonly taken for anti-aging and longevity, hair graying and hair loss, general tonic for vitality.Based on those ingredients, 1,257 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Chinese Knotweed Root Extract, Dry. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.
Check Your Meds Against Chinese Knotweed by Hawaii Pharm
Ask about any prescription or over-the-counter medication and we check it for interactions with Chinese Knotweed by Hawaii Pharm — and tell you which ingredient is responsible.
AI summaries are generated from our interaction database for education only — always confirm with your pharmacist. How we use AI
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HelloPharmacist Scorecard of Chinese Knotweed by Hawaii Pharm
Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.
What’s inside
Full disclosure
This liquid contains one active ingredient: Chinese Knotweed Root Extract in dry form (from fo-ti). The preparation is made with alcohol, water, and glycerin as inactive ingredients.
Does it work?
Couldn't assess
The evidence we hold does not establish effectiveness for fo-ti in any of the conditions studied — age-related cognitive decline, hair loss (androgenic alopecia), Alzheimer disease, osteoporosis, and cardiovascular disease all have insufficient reliable evidence to rate. That doesn't mean it doesn't work; it means the data we have isn't solid enough to say.
How safe is it?
Well-documented data
Fo-ti has been linked to liver injury and is not considered safe to use. The medical literature documents around 450 cases of hepatitis linked to fo-ti across both processed and unprocessed forms, occurring at a wide range of doses and durations — outcomes have ranged from full recovery to cirrhosis and liver failure.
The most common side effects from unprocessed fo-ti are abdominal pain, diarrhea, nausea, and vomiting. The safety data advises against use during pregnancy or breastfeeding, as there isn't enough information to say it's safe in either situation.
Meds to double-check
Moderate interaction found
Stop and check with your pharmacist if you take blood thinners (anticoagulants) like warfarin, digoxin for heart rhythm, stimulant laxatives, diuretics (water pills), sulindac, or any drug processed by liver enzymes CYP2C8 or CYP2B6. All of these carry documented moderate interaction risk with fo-ti.
The bottom line
Scorecard at a glanceFully disclosed formula with no assessable stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.
Because fo-ti carries documented risk of liver injury and interacts with blood thinners and other medications, this is not a product to start on your own. If you're considering it, talk with your pharmacist or doctor first — they'll want to know your full medication list and liver health before you take it.
Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI
Assessment coverage: 1 of 1 active ingredient matched to our full ingredient reviews (monographs). Based on the product label dated Nov 22, 2023.
This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed
General information
Key facts about Chinese Knotweed, straight from the product label.
| Brand | Hawaii Pharm |
|---|---|
| Barcode (UPC) | 840253613639 |
| Net contents | 4 Fluid Ounce(s); 120 mL |
| Market status | On market |
| Date entered into DSLD | Nov 22, 2023 |
| DSLD ID | 301381 |
| Product type | Botanical |
| Supplement form | Liquid |
| Dietary claims / uses | All Other, Structure/Function |
| Intended target group(s) | Adult (18 - 50 Years), Gluten Free |
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.
Supplement Facts
The label details for Chinese Knotweed by Hawaii Pharm, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| Chinese Knotweed Root Extract, Dry | 983 mg | -- |
Other ingredients: Alcohol, Water, Glycerin
Tap any ingredient to jump to its full detail below.
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
Brand IP Statement(s)
Hawaii Pharm Herbal Extract Highest quality since 2008
Suggested/Recommended/Usage/Directions
Suggested use: Shake well before using. For adults add about 20-30 drops (0.7-1 mL, one full squeeze of the dropper bulb) to some juice or water, up to 4 times a day.
Precautions
Warning: We recommend to seek expert medical advice before taking.
Do not use if you are allergic to any ingredients.
Consult your physician before giving to children under 18, during pregnancy, if nursing or taking medications.
Consult your physician before giving to children under 18, during pregnancy, if nursing or taking medications.
May affect the ability to drive and operate machinery. May have contraindications, can cause side effects and adverse reactions. Do not use if seal is broken or missing.
Keep out of the reach of children!
Storage
Store in a cool dry place.
Seals/Symbols
cGMP Made in compliance with cGMP 21 CFR 111 in an FDA registered and inspected facility.
Organic Alcohol Based USA Made in United States of America
FDA Disclaimer Statement
This product has not been evaluated by the FDA and is not intended to diagnose, treat, cure or prevent any disease.
General Statements
Scan this QR-code to get 15% discount on your next purchase. Limited time deal.
Formula
Polygonum multiflorum
Organic Alcohol Based
Formulation
Only natural ingredients Purity is laboratory tested and verified
All the raw materials are gluten-free by their nature No artificial colors, flavors, or preservatives
Not tested on animals
Organic Alcohol Based
Made in USA, Hawaii
FDA Statement of Identity
Herbal Supplement
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
Chinese Knotweed by Hawaii Pharm label
The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.
Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.
View the full label (PDF)The Ingredients in Chinese Knotweed by Hawaii Pharm
This is the 1 active ingredient this product is made of. Select it to open its full monograph.
Serving size0.7 mL Dosage formLiquid Servings per container120 Amounts shown are per serving.
Chinese Knotweed Root Extract, Dry
Interacts with1,257 drugs
Fo-ti (He Shou Wu) is a root used in traditional Chinese medicine, often promoted for healthy aging and hair. High-quality human evidence for these be...
Chinese Knotweed Root Extract, Dry monograph & interactionsOther (inactive) ingredients: Alcohol, Water, Glycerin. These complete the product’s ingredient list but are not active constituents.
Chinese Knotweed by Hawaii Pharm Drug Interactions
HelloPharmacist Interaction Report
Chinese Knotweed by Hawaii Pharm contains fo-ti root extract, which carries documented interactions with several medication types.
The most serious concern is with blood thinners (anticoagulants) like warfarin — fo-ti has been linked to cases of acute liver failure that can boost the effects of these drugs and raise bleeding risk. In one documented case, a patient stable on warfarin developed acute hepatitis and a dangerously elevated clotting measure after 90 days of fo-ti use.
Read the full breakdown — every affected drug type, severity by severity
Fo-ti also interacts with digoxin (a heart medication), stimulant laxatives, and diuretics — all moderately concerning because the raw plant form contains compounds with laxative effects that can trigger diarrhea and electrolyte loss. It may also affect how your body processes sulindac (an anti-inflammatory), and several other drug types broken down by liver enzymes (CYP2C8 and CYP2B6 substrates), though these have not been confirmed in humans.
Altogether, these interactions span 1,258 individual medications. Before you start this product, run your exact medications through the checker on this page.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against Chinese Knotweed?
Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.
Go to the checkerIngredients driving the most interactions
Individual Drug Interactions
The ingredients in Chinese Knotweed interact with 1,257 drugs. Click any drug to see the details.
1 of the 1 ingredient in Chinese Knotweed interact with drugs. Each result below shows which ingredient is responsible. Chinese Knotweed Root Extract, Dry
6-mercaptopurinePurinethol
How 6-mercaptopurine interacts with Chinese Knotweed — through 1 ingredient. Tap an ingredient for the detail:
Chinese Knotweed Root Extract, DryHepatotoxic Drugs Moderate
Interaction Summary
Theoretically, fo-ti might increase the risk of liver damage when taken with hepatotoxic drugs.
Read the full Chinese Knotweed Root Extract, Dry + 6-mercaptopurine interactionAdo-trastuzumab EmtansineKadcyla
How Ado-trastuzumab Emtansine interacts with Chinese Knotweed — through 1 ingredient. Tap an ingredient for the detail:
Chinese Knotweed Root Extract, DryCytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
Theoretically, fo-ti might increase the levels and clinical effects of drugs metabolized by CYP3A4.
Read the full Chinese Knotweed Root Extract, Dry + Ado-trastuzumab Emtansine interactionAbacavir Sulfate, Dolutegravir, LamivudineTriumeq
How Abacavir Sulfate, Dolutegravir, Lamivudine interacts with Chinese Knotweed — through 1 ingredient. Tap an ingredient for the detail:
Chinese Knotweed Root Extract, DryHepatotoxic Drugs Moderate
Interaction Summary
Theoretically, fo-ti might increase the risk of liver damage when taken with hepatotoxic drugs.
Read the full Chinese Knotweed Root Extract, Dry + Abacavir Sulfate, Dolutegravir, Lamivudine interactionAbacavir, LamivudineEpzicom
How Abacavir, Lamivudine interacts with Chinese Knotweed — through 1 ingredient. Tap an ingredient for the detail:
Chinese Knotweed Root Extract, DryHepatotoxic Drugs Moderate
Interaction Summary
Theoretically, fo-ti might increase the risk of liver damage when taken with hepatotoxic drugs.
Read the full Chinese Knotweed Root Extract, Dry + Abacavir, Lamivudine interactionAbciximabReoPro
How Abciximab interacts with Chinese Knotweed — through 1 ingredient. Tap an ingredient for the detail:
Chinese Knotweed Root Extract, DryAnticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Fo-ti has been linked to cases of acute liver failure which can decrease clotting factor production and increase the effects of anticoagulants.
Read the full Chinese Knotweed Root Extract, Dry + Abciximab interactionAbemaciclibVerzenio
How Abemaciclib interacts with Chinese Knotweed — through 1 ingredient. Tap an ingredient for the detail:
Chinese Knotweed Root Extract, DryCytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
Theoretically, fo-ti might increase the levels and clinical effects of drugs metabolized by CYP3A4.
Read the full Chinese Knotweed Root Extract, Dry + Abemaciclib interactionAbiraterone
How Abiraterone interacts with Chinese Knotweed — through 1 ingredient. Tap an ingredient for the detail:
Chinese Knotweed Root Extract, DryHepatotoxic Drugs, Cytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
Theoretically, fo-ti might increase the risk of liver damage when taken with hepatotoxic drugs.
Read the full Chinese Knotweed Root Extract, Dry + Abiraterone interactionAbiraterone AcetateYonsa, Zytiga
How Abiraterone Acetate interacts with Chinese Knotweed — through 1 ingredient. Tap an ingredient for the detail:
Chinese Knotweed Root Extract, DryCytochrome P450 3a4 (cyp3a4) Substrates, Hepatotoxic Drugs Moderate
Interaction Summary
Theoretically, fo-ti might increase the levels and clinical effects of drugs metabolized by CYP3A4.
Read the full Chinese Knotweed Root Extract, Dry + Abiraterone Acetate interactionAbrocitinibCibinqo
How Abrocitinib interacts with Chinese Knotweed — through 1 ingredient. Tap an ingredient for the detail:
Chinese Knotweed Root Extract, DryAnticoagulant/antiplatelet Drugs, Cytochrome P450 2c9 (cyp2c9) Substrates +1 Moderate
Interaction Summary
Fo-ti has been linked to cases of acute liver failure which can decrease clotting factor production and increase the effects of anticoagulants.
Read the full Chinese Knotweed Root Extract, Dry + Abrocitinib interactionAcalabrutinibCalquence
How Acalabrutinib interacts with Chinese Knotweed — through 1 ingredient. Tap an ingredient for the detail:
Chinese Knotweed Root Extract, DryCytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
Theoretically, fo-ti might increase the levels and clinical effects of drugs metabolized by CYP3A4.
Read the full Chinese Knotweed Root Extract, Dry + Acalabrutinib interactionAcarboseGlucobay, Prandase, Precose
How Acarbose interacts with Chinese Knotweed — through 1 ingredient. Tap an ingredient for the detail:
Chinese Knotweed Root Extract, DryAntidiabetes Drugs, Hepatotoxic Drugs Moderate
Interaction Summary
Theoretically, fo-ti might increase the risk of hypoglycemia when taken with antidiabetes drugs.
Read the full Chinese Knotweed Root Extract, Dry + Acarbose interactionAcebutololRhotral, Sectral
How Acebutolol interacts with Chinese Knotweed — through 1 ingredient. Tap an ingredient for the detail:
Chinese Knotweed Root Extract, DryHepatotoxic Drugs Moderate
Interaction Summary
Theoretically, fo-ti might increase the risk of liver damage when taken with hepatotoxic drugs.
Read the full Chinese Knotweed Root Extract, Dry + Acebutolol interactionAcenocoumarolSintrom
How Acenocoumarol interacts with Chinese Knotweed — through 1 ingredient. Tap an ingredient for the detail:
Chinese Knotweed Root Extract, DryAnticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Fo-ti has been linked to cases of acute liver failure which can decrease clotting factor production and increase the effects of anticoagulants.
Read the full Chinese Knotweed Root Extract, Dry + Acenocoumarol interactionAcetaminophenChildren's Tylenol, Children's Tylenol Meltaways, Tylenol, Tylenol Ex Strength
How Acetaminophen interacts with Chinese Knotweed — through 1 ingredient. Tap an ingredient for the detail:
Chinese Knotweed Root Extract, DryCytochrome P450 1a2 (cyp1a2) Substrates, Hepatotoxic Drugs Moderate
Interaction Summary
Theoretically, fo-ti might increase or decrease the levels and clinical effects of drugs metabolized by CYP1A2.
Read the full Chinese Knotweed Root Extract, Dry + Acetaminophen interactionAcetaminophen, AspirinGemnisyn
How Acetaminophen, Aspirin interacts with Chinese Knotweed — through 1 ingredient. Tap an ingredient for the detail:
Chinese Knotweed Root Extract, DryHepatotoxic Drugs, Cytochrome P450 1a2 (cyp1a2) Substrates +1 Moderate
Interaction Summary
Theoretically, fo-ti might increase the risk of liver damage when taken with hepatotoxic drugs.
Read the full Chinese Knotweed Root Extract, Dry + Acetaminophen, Aspirin interactionAcetaminophen, Aspirin, CaffeineExcedrin, Excedrin Extra Strength, Excedrin Migraine
How Acetaminophen, Aspirin, Caffeine interacts with Chinese Knotweed — through 1 ingredient. Tap an ingredient for the detail:
Chinese Knotweed Root Extract, DryAnticoagulant/antiplatelet Drugs, Cytochrome P450 1a2 (cyp1a2) Substrates +2 Moderate
Interaction Summary
Fo-ti has been linked to cases of acute liver failure which can decrease clotting factor production and increase the effects of anticoagulants.
Read the full Chinese Knotweed Root Extract, Dry + Acetaminophen, Aspirin, Caffeine interactionAcetaminophen, Brompheniramine, PhenylpropanolamineDimetapp Cold and Flu
How Acetaminophen, Brompheniramine, Phenylpropanolamine interacts with Chinese Knotweed — through 1 ingredient. Tap an ingredient for the detail:
Chinese Knotweed Root Extract, DryCytochrome P450 1a2 (cyp1a2) Substrates, Hepatotoxic Drugs Moderate
Interaction Summary
Theoretically, fo-ti might increase or decrease the levels and clinical effects of drugs metabolized by CYP1A2.
Read the full Chinese Knotweed Root Extract, Dry + Acetaminophen, Brompheniramine, Phenylpropanolamine interactionAcetaminophen, ButalbitalAxocet, Bancap, Bucet, Butex Forte, Esgic CF, Orbivan CF +5 more
How Acetaminophen, Butalbital interacts with Chinese Knotweed — through 1 ingredient. Tap an ingredient for the detail:
Chinese Knotweed Root Extract, DryHepatotoxic Drugs, Cytochrome P450 1a2 (cyp1a2) Substrates Moderate
Interaction Summary
Theoretically, fo-ti might increase the risk of liver damage when taken with hepatotoxic drugs.
Read the full Chinese Knotweed Root Extract, Dry + Acetaminophen, Butalbital interactionAcetaminophen, Butalbital, CaffeineEsgic, Esgic Plus, Fiogesic, Fioricet, Repan, Tecnal +1 more
How Acetaminophen, Butalbital, Caffeine interacts with Chinese Knotweed — through 1 ingredient. Tap an ingredient for the detail:
Chinese Knotweed Root Extract, DryCytochrome P450 1a2 (cyp1a2) Substrates, Cytochrome P450 3a4 (cyp3a4) Substrates +1 Moderate
Interaction Summary
Theoretically, fo-ti might increase or decrease the levels and clinical effects of drugs metabolized by CYP1A2.
Read the full Chinese Knotweed Root Extract, Dry + Acetaminophen, Butalbital, Caffeine interactionAcetaminophen, Butalbital, Caffeine, CodeineEsgic with Codeine, Fioricet w/ Codeine
How Acetaminophen, Butalbital, Caffeine, Codeine interacts with Chinese Knotweed — through 1 ingredient. Tap an ingredient for the detail:
Chinese Knotweed Root Extract, DryHepatotoxic Drugs, Cytochrome P450 1a2 (cyp1a2) Substrates +2 Moderate
Interaction Summary
Theoretically, fo-ti might increase the risk of liver damage when taken with hepatotoxic drugs.
Read the full Chinese Knotweed Root Extract, Dry + Acetaminophen, Butalbital, Caffeine, Codeine interactionAcetaminophen, Butalbital, CodeineBancap w/ Codeine
How Acetaminophen, Butalbital, Codeine interacts with Chinese Knotweed — through 1 ingredient. Tap an ingredient for the detail:
Chinese Knotweed Root Extract, DryCytochrome P450 2d6 (cyp2d6) Substrates, Hepatotoxic Drugs +1 Moderate
Interaction Summary
Theoretically, fo-ti may increase the levels and clinical effects of drugs metabolized by CYP2D6.
Read the full Chinese Knotweed Root Extract, Dry + Acetaminophen, Butalbital, Codeine interactionAcetaminophen, Butalbital, Codeine PhosphatePhrenilin #3
How Acetaminophen, Butalbital, Codeine Phosphate interacts with Chinese Knotweed — through 1 ingredient. Tap an ingredient for the detail:
Chinese Knotweed Root Extract, DryCytochrome P450 1a2 (cyp1a2) Substrates, Cytochrome P450 2d6 (cyp2d6) Substrates +1 Moderate
Interaction Summary
Theoretically, fo-ti might increase or decrease the levels and clinical effects of drugs metabolized by CYP1A2.
Read the full Chinese Knotweed Root Extract, Dry + Acetaminophen, Butalbital, Codeine Phosphate interactionAcetaminophen, Caffeine, Chlorpheniramine, Hydrocodone, PhenylephrineHycomine Compound
How Acetaminophen, Caffeine, Chlorpheniramine, Hydrocodone, Phenylephrine interacts with Chinese Knotweed — through 1 ingredient. Tap an ingredient for the detail:
Chinese Knotweed Root Extract, DryHepatotoxic Drugs, Cytochrome P450 1a2 (cyp1a2) Substrates +2 Moderate
Interaction Summary
Theoretically, fo-ti might increase the risk of liver damage when taken with hepatotoxic drugs.
Read the full Chinese Knotweed Root Extract, Dry + Acetaminophen, Caffeine, Chlorpheniramine, Hydrocodone, Phenylephrine interactionAcetaminophen, Caffeine, CodeineGesic C15, Gesic C30, Gesic C8, Lenoltec 1, Lenoltec 2, Lenoltec 3 +1 more
How Acetaminophen, Caffeine, Codeine interacts with Chinese Knotweed — through 1 ingredient. Tap an ingredient for the detail:
Chinese Knotweed Root Extract, DryCytochrome P450 3a4 (cyp3a4) Substrates, Hepatotoxic Drugs +2 Moderate
Interaction Summary
Theoretically, fo-ti might increase the levels and clinical effects of drugs metabolized by CYP3A4.
Read the full Chinese Knotweed Root Extract, Dry + Acetaminophen, Caffeine, Codeine interactionAcetaminophen, Caffeine, Codeine, SalicylamideCodalan No.1, Codalan No.2, Codalan No.3
How Acetaminophen, Caffeine, Codeine, Salicylamide interacts with Chinese Knotweed — through 1 ingredient. Tap an ingredient for the detail:
Chinese Knotweed Root Extract, DryCytochrome P450 1a2 (cyp1a2) Substrates, Cytochrome P450 3a4 (cyp3a4) Substrates +2 Moderate
Interaction Summary
Theoretically, fo-ti might increase or decrease the levels and clinical effects of drugs metabolized by CYP1A2.
Read the full Chinese Knotweed Root Extract, Dry + Acetaminophen, Caffeine, Codeine, Salicylamide interactionAcetaminophen, Caffeine, DihydrocodeineDHC Plus, Panlor DC, Panlor SS
How Acetaminophen, Caffeine, Dihydrocodeine interacts with Chinese Knotweed — through 1 ingredient. Tap an ingredient for the detail:
Chinese Knotweed Root Extract, DryHepatotoxic Drugs, Cytochrome P450 1a2 (cyp1a2) Substrates +2 Moderate
Interaction Summary
Theoretically, fo-ti might increase the risk of liver damage when taken with hepatotoxic drugs.
Read the full Chinese Knotweed Root Extract, Dry + Acetaminophen, Caffeine, Dihydrocodeine interactionAcetaminophen, Caffeine, IsomethepteneMigralam
How Acetaminophen, Caffeine, Isometheptene interacts with Chinese Knotweed — through 1 ingredient. Tap an ingredient for the detail:
Chinese Knotweed Root Extract, DryCytochrome P450 3a4 (cyp3a4) Substrates, Hepatotoxic Drugs +1 Moderate
Interaction Summary
Theoretically, fo-ti might increase the levels and clinical effects of drugs metabolized by CYP3A4.
Read the full Chinese Knotweed Root Extract, Dry + Acetaminophen, Caffeine, Isometheptene interactionAcetaminophen, Caffeine, PyrilamineMidol Max Strength Menstrual
How Acetaminophen, Caffeine, Pyrilamine interacts with Chinese Knotweed — through 1 ingredient. Tap an ingredient for the detail:
Chinese Knotweed Root Extract, DryCytochrome P450 1a2 (cyp1a2) Substrates, Cytochrome P450 3a4 (cyp3a4) Substrates +2 Moderate
Interaction Summary
Theoretically, fo-ti might increase or decrease the levels and clinical effects of drugs metabolized by CYP1A2.
Read the full Chinese Knotweed Root Extract, Dry + Acetaminophen, Caffeine, Pyrilamine interactionAcetaminophen, Chlorpheniramine Maleate, Dextromethorphan HbrVicks Formula 44M Cough, Cold & Flu Relief
How Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan Hbr interacts with Chinese Knotweed — through 1 ingredient. Tap an ingredient for the detail:
Chinese Knotweed Root Extract, DryHepatotoxic Drugs, Cytochrome P450 1a2 (cyp1a2) Substrates +2 Moderate
Interaction Summary
Theoretically, fo-ti might increase the risk of liver damage when taken with hepatotoxic drugs.
Read the full Chinese Knotweed Root Extract, Dry + Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan Hbr interactionAcetaminophen, Chlorpheniramine, Codeine, PhenylephrineColrex
How Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine interacts with Chinese Knotweed — through 1 ingredient. Tap an ingredient for the detail:
Chinese Knotweed Root Extract, DryCytochrome P450 2d6 (cyp2d6) Substrates, Hepatotoxic Drugs +2 Moderate
Interaction Summary
Theoretically, fo-ti may increase the levels and clinical effects of drugs metabolized by CYP2D6.
Read the full Chinese Knotweed Root Extract, Dry + Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine interactionEach ingredient & the kinds of drugs it affects
For each ingredient in Chinese Knotweed with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.
Chinese Knotweed Root Extract, Dry
Anticoagulant/Antiplatelet Drugs
Fo-ti has been linked to cases of acute liver failure which can decrease clotting factor production and increase the effects of anticoagulants. In one case, a patient who had been stable on warfarin presented with acute hepatitis and an INR elevated to 14.98. The patient had been taking fo-ti for 90 days prior to admission. Discontinuation of warfarin and fo-ti lead to a decrease in the INR and full recovery. Theoretically, concomitant use of fo-ti with anticoagulant or antiplatelet drugs may increase the risk of bleeding in some patients. Until more is known, monitor patients taking fo-ti and drugs that affect bleeding.
Some of these drugs include aspirin, clopidogrel (Plavix), dalteparin (Fragmin), dipyridamole (Persantine), enoxaparin (Lovenox), heparin, ticlopidine (Ticlid), warfarin (Coumadin), and others.
Antidiabetes Drugs
Theoretically, fo-ti might increase the risk of hypoglycemia when taken with antidiabetes drugs.
Fo-ti reportedly has hypoglycemic effects.
Contraceptive Drugs
Theoretically, taking large amounts of fo-ti might interfere with contraceptive drugs due to competition for estrogen receptors.
In vitro research suggests that fo-ti extract has estrogenic activity.
Cytochrome P450 1A2 (Cyp1A2) Substrates
Theoretically, fo-ti might increase or decrease the levels and clinical effects of drugs metabolized by CYP1A2.
In vitro research suggests that fo-ti might inhibit CYP1A2. Additionally, in vitro research suggests that the degree of CYP1A2 inhibition depends on the type of fo-ti extract (i.e., the raw plant leads to greater inhibition than extensively processed extracts). However, in an animal study, an aqueous extract of fo-ti inhibited CYP1A2 while an alcoholic extract of fo-ti induced CYP1A2. Induction or inhibition of CYP1A2 by fo-ti has not been reported in humans.
Cytochrome P450 2B6 (Cyp2B6) Substrates
Theoretically, fo-ti might increase the levels and clinical effects of drugs metabolized by CYP2B6.
Animal research suggests that fo-ti might inhibit CYP2B6. One in vitro study suggests that the degree of CYP2B6 inhibition may depend on the type of fo-ti extract (i.e., the raw plant leads to greater inhibition than extensively processed extracts). However, this interaction has not been reported in humans.
Cytochrome P450 2C19 (Cyp2C19) Substrates
Theoretically, fo-ti may increase the levels and clinical effects of drugs metabolized by CYP2C19.
Animal and in vitro research suggests that fo-ti may inhibit CYP2C19. An in vitro study suggests that the degree of CYP2C19 inhibition may depend on the type of fo-ti extract (i.e., the raw plant leads to greater inhibition than extensively processed extracts). However, this interaction has not been reported in humans.
Cytochrome P450 2C8 (Cyp2C8) Substrates
Theoretically, fo-ti might increase the levels and clinical effects of drugs metabolized by CYP2C8.
In vitro research suggests that fo-ti might inhibit CYP2C8. However, this interaction has not been reported in humans.
Cytochrome P450 2C9 (Cyp2C9) Substrates
Theoretically, fo-ti may increase the levels and clinical effects of drugs metabolized by CYP2C9.
Animal and in vitro research suggests that fo-ti may inhibit CYP2C9. However, this interaction has not been reported in humans.
Cytochrome P450 2D6 (Cyp2D6) Substrates
Theoretically, fo-ti may increase the levels and clinical effects of drugs metabolized by CYP2D6.
Animal research suggests that fo-ti might inhibit CYP2D6. Additionally, an in vitro study suggests that the degree of CYP2D6 inhibition may depend on the type of fo-ti extract (i.e., the raw plant leads to greater inhibition than extensively processed extracts). However, this interaction has not been reported in humans.
Cytochrome P450 3A4 (Cyp3A4) Substrates
Theoretically, fo-ti might increase the levels and clinical effects of drugs metabolized by CYP3A4.
In vitro research suggests that fo-ti might inhibit CYP3A4. One in vitro study suggests that the degree of CYP3A4 inhibition may depend on the type of fo-ti extract (i.e., the raw plant leads to greater inhibition than extensively processed extracts). However, this evidence conflicts with animal research suggesting that fo-ti does not inhibit CYP3A4. This interaction has not been reported in humans.
Digoxin (Lanoxin)
Theoretically, fo-ti, particularly raw fo-ti root, might increase the risk of hypokalemia and cardiotoxicity when taken with digoxin.
Raw fo-ti root contains anthraquinone derivatives, which might have stimulant laxative effects. In vitro research shows that fermented and processed fo-ti root have reduced laxative effects compared with raw fo-ti root.
Diuretic Drugs
Theoretically, fo-ti, particularly raw fo-ti root, might increase the risk of hypokalemia when taken with diuretic drugs.
Raw fo-ti root contains anthraquinone derivatives, which might have stimulant laxative effects and compound diuretic-induced potassium loss. In vitro research shows that fermented and processed fo-ti root have reduced laxative effects compared with raw fo-ti root.
Estrogens
Theoretically, taking large amounts of fo-ti might interfere with hormone replacement therapy through competition for estrogen receptors.
In vitro research suggests that fo-ti extract has estrogenic activity.
Hepatotoxic Drugs
Theoretically, fo-ti might increase the risk of liver damage when taken with hepatotoxic drugs.
Fo-ti has been linked to liver damage in many reports.
Stimulant Laxatives
Theoretically, fo-ti, particularly raw fo-ti root, might increase the risk of fluid and electrolyte depletion when taken with stimulant laxatives.
Raw fo-ti root contains anthraquinone derivatives, which might have stimulant laxative effects. However, in vitro research shows that fermented and processed fo-ti root have reduced laxative effects compared with raw fo-ti root.
Sulindac (Clinoril)
Theoretically, fo-ti might increase or decrease the levels and clinical effects of sulindac.
Animal research suggests that the type of fo-ti extract might affect the levels of sulindac differently; the raw plant may increase levels, but processed parts may decrease levels. Induction or inhibition of CYP1A2 by fo-ti has not been reported in humans.
Warfarin (Coumadin)
Theoretically, fo-ti might increase the effects and adverse effects of warfarin.
Fo-ti may have stimulant laxative effects and cause diarrhea, especially when the raw or unprocessed fo-ti root is used. Diarrhea can increase the effects of warfarin, increase international normalized ratio (INR), and increase the risk of bleeding. Also, fo-ti has been linked to cases of acute liver failure which can decrease clotting factor production and increase the effects of warfarin. In one case, a patient who had been stable on warfarin presented with acute hepatitis and an INR elevated to 14.98. The patient had been taking fo-ti for 90 days prior to admission. Discontinuation of warfarin and fo-ti lead to a decrease in the INR and full recovery.
Brand information
Manufacturer and brand details for Chinese Knotweed, from the product label.
Hawaii Pharm
See all Hawaii Pharm products- Name
- Hawaii Pharm LLC
- Street Address
- 510 Sumner St. Ste. 613
- City
- Honolulu
- State
- HI
- ZipCode
- 96817
- Phone Number
- 888-854-2924
- Web Address
- www.hawaiipharm.com
Chinese Knotweed by Hawaii Pharm: Common Questions
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The Full Monographs Behind Chinese Knotweed’s Ingredients
Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.
Sources & How We Checked
Chinese Knotweed's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.
- NIH Dietary Supplement Label Database (DSLD) — The official product label on file for this supplement.
- Natural Medicines (Therapeutic Research Center) — Evidence-graded clinical reference behind the ingredient interaction data.
Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.
The 28 references behind this product’s interaction data
Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.
Fo-ti 28 references
- Foster S, Tyler VE. Tyler's Honest Herbal: A Sensible Guide to the Use of Herbs and Related Remedies. 3rd ed., Binghamton, NY: Haworth Herbal Press, 1993.
- McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
- Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
- Covington TR, et al. Handbook of Nonprescription Drugs. 11th ed. Washington, DC: American Pharmaceutical Association, 1996.
- Park GJ, Mann SP, Ngu MC. Acute hepatitis induced by Shou-Wu-Pian, a herbal product derived from Polygonum multiflorum. J Gastroenterol Hepatol 2001;16:115-7.
- But PP, Tomlinson B, Lee KL. Hepatitis related to the Chinese medicine Shou-wu-pian manufactured from Polygonum multiflorum. Vet Hum Toxicol 1996;38:280-2.
- Oerter Klein KO, Janfaza M, Wong JA, Chang RJ. Estrogen bioactivity in Fo-Ti and other herbs used for their estrogen-like effects as determined by a recombinant cell bioassay. J Clin Endocrinol Metab 2003;88:4077-9.. PubMed
- Unger M, Frank A. Simultaneous determination of the inhibitory potency of herbal extracts on the activity of six major cytochrome P450 enzymes using liquid chromatography/mass spectrometry and automated online extraction. Rapid Commun Mass Spectrom 2004;1 PubMed
- UK Medicines and Healthcare Products Regulatory Agency. Polygonum multiflorum and liver reactions. April 2006. Available at: www.mhra.gov.uk/home/idcplg?IdcService= SS_GET_PAGE&useSecondary=true&ssDocName= CON2023590&ssTargetNodeId= 833 (Accessed 10 May 2
- Panis B, Wong DR, Hooymans PM, De Smet PA, Rosias PP. Recurrent toxic hepatitis in a Caucasian girl related to the use of Shou-Wu-Pian, a Chinese herbal preparation. J Pediatr Gastroenterol Nutr 2005;41:256-8. PubMed
- Mazzanti G, Battinelli L, Daniele C, et al. New case of acute hepatitis following the consumption of Shou Wu Pian, a Chinese herbal product derived from Polygonum multiflorum. Ann Intern Med 2004;140:E589-90.
- Cardenas A, Restrepo JC, Sierra F, Correa G. Acute hepatitis due to shen-min: a herbal product derived from Polygonum multiflorum. J Clin Gastroenterol 2006;40:629-32. PubMed
- Zhang CZ, Wang SX, Zhang Y, et al. In vitro estrogenic activities of Chinese medicinal plants traditionally used for the management of menopausal symptoms. J Ethnopharmacol 2005;98:295-300. PubMed
- Laird AR, Ramchandani N, deGoma EM, et al. Acute hepatitis associated with the use of an herbal supplement (Polygonum multiflorum) mimicking iron-overload syndrome. J Clin Gastroenterol 2008;42:861-2. PubMed
- Jung KA, Min HJ, Yoo SS, et al. Drug-Induced Liver Injury: Twenty Five Cases of Acute Hepatitis Following Ingestion of Polygonum multiflorum Thunb. Gut Liver 2011;5(4):493-9. PubMed
- Kang, S. C., Lee, C. M., Choi, H., Lee, J. H., Oh, J. S., Kwak, J. H., and Zee, O. P. Evaluation of oriental medicinal herbs for estrogenic and antiproliferative activities. Phytother Res 2006;20(11):1017-1019. PubMed
- Yuen, M. F., Tam, S., Fung, J., Wong, D. K., Wong, B. C., and Lai, C. L. Traditional Chinese medicine causing hepatotoxicity in patients with chronic hepatitis B infection: a 1-year prospective study. Aliment.Pharmacol.Ther 10-15-2006;24(8):1179-1186. PubMed
- Zhang, L., Yang, X., Sun, Z., and Qu, Y. [Retrospective study of adverse events of Polygonum multiflorum and risk control]. Zhongguo Zhong.Yao Za Zhi. 2009;34(13):1724-1729.
- Bae, S. H., Kim, D. H., Bae, Y. S., Lee, K. J., Kim, D. W., Yoon, J. B., Hong, J. H., and Kim, S. H. [Toxic hepatitis associated with Polygoni multiflori]. Korean J.Hepatol. 2010;16(2):182-186. PubMed
- Furukawa, M., Kasajima, S., Nakamura, Y., Shouzushima, M., Nagatani, N., Takinishi, A., Taguchi, A., Fujita, M., Niimi, A., Misaka, R., and Nagahara, H. Toxic hepatitis induced by show-wu-pian, a Chinese herbal preparation. Intern.Med. 2010;49(15):1537-1 PubMed
- McGuffin, M., Hobbs, C., Upton, R., and Goldberg, A. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC;1997.
- Dong H, Slain D, Cheng J, Ma W, Liang W. Eighteen cases of liver injury following ingestion of Polygonum multiflorum. Complement Ther Med 2014;22(1):70-4. PubMed
- Lei X, Chen J, Ren J, et al. Liver damage associated with Polygonum multiflorum Thunb.: a systematic review of case reports and case series. Evid Based Complement Alternat Med 2015;2015:459749.
- Ma KF, Zhang XG, Jia HY. CYP1A2 polymorphism in Chinese patients with acute liver injury induced by Polygonum multiflorum. Genet Mol Res 2014;13(3):5637-43. PubMed
- Zhang Y, Ding T, Diao T, Deng M, Chen S. Effects of Polygonum multiflorum on the activity of cytochrome P450 isoforms in rats. Pharmazie 2015;70(1):47-54. DOI
- Yu J, Xie J, Mao XJ, et al. Comparison of laxative and antioxidant activities of raw, processed and fermented Polygoni multiflori radix. Chin J Nat Med 2012;10(1):63-7. DOI
- Shao YL, Ma CM, Wu JM, Guo FC, Zhang SC. Concurrent severe hepatotoxicity and agranulocytosis induced by Polygonum multiflorum: A case report. World J Clin Cases 2022;10(27):9921-9928.
- Xing Y, Yu Q, Zhou L, et al. Cytochrome P450-mediated herb-drug interaction (HDI) of Polygonum multiflorum Thunb. based on pharmacokinetic studies and in vitro inhibition assays. Phytomedicine 2023;112:154710. PubMed
Parts of this content are provided by the Therapeutic Research Center, LLC.
DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.
© 2021 Therapeutic Research Center, LLC