Major interaction on record — check this product against your medications before combining. Based on 4 of 6 ingredients. Check your meds →
Dietary supplement

Tong Chang Pian Constipass Ingredients & Drug Interactions

by Guang Ci Tang

Tong Chang Pian Constipass label
See full label image
Tablet Or Pill Category: Botanical
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 30, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Tong Chang Pian Constipass 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

The interaction bottom line Most serious interaction: Major

Tong Chang Pian Constipass is a dietary supplement by Guang Ci Tang with 6 active ingredients. Its ingredients are commonly taken for menopause symptoms, menstrual cramps and irregular periods, premenstrual syndrome (pms).Based on those ingredients, 1,401 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Fo-Ti, Cured, Hemp, Chinese Rhubarb. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Tong Chang Pian Constipass by Guang Ci Tang

Ask about any prescription or over-the-counter medication and we check it for interactions with Tong Chang Pian Constipass by Guang Ci Tang — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Tong Chang Pian Constipass by Guang Ci Tang

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.

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Sep 17, 2026

What’s inside

Low disclosure
Ingredient Transparency · database check
Low

Most active ingredients don't disclose an individual amount — you can't tell how much of each you're getting.

Why this rating?
  • The label discloses an exact amount for 0 of its 6 active ingredients.
  • “Proprietary Blend” is a proprietary blend — the label gives one combined amount (1,000 mg) without saying how much of each component you get.

Tong Chang Pian Constipass contains 6 ingredients, including a proprietary blend with dong quai, notopterygium, peach, Chinese rhubarb, fo-ti (cured), and hemp. Dong quai and Chinese rhubarb are traditional tonics and digestive aids; fo-ti and hemp round out the botanical mix.

The product also contains inactive ingredients — corn starch, dextrin, and magnesium stearate — which serve as fillers and binders in the tablet.

Does it work?

Insufficient evidence
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed
Insufficient

There isn't enough reliable clinical evidence to rate this product's ingredients for its stated purpose.

Why this rating?
  • The label markets this product for: constipation relief.
  • We looked for evidence on: Constipation.
  • The closest evidence on file: Rhubarb is rated "Insufficient Reliable Evidence To Rate" for Constipation (Natural Medicines).
  • Also on file: Hemp is rated "Insufficient Reliable Evidence To Rate" for Constipation.

The data we hold shows insufficient evidence for most uses claimed for these ingredients. Dong quai, fo-ti, and hemp lack reliable evidence for constipation, anemia, bone health, and other common applications.

Chinese rhubarb is rated possibly effective for pancreatitis and menopausal symptoms, but we have no established evidence that this product works for constipation — the condition its name suggests it addresses. Before relying on it, talk with your doctor or pharmacist about whether the research supports its use for your particular concern.

The evidence, ingredient by ingredient Dong Quai Rhubarb Fo-ti Hemp

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 4 of the 4 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 4 of 4.
  • General safety write-ups exist for 4 of 4.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Dong quai is generally well tolerated orally, though burping and flatulence are the most common side effects; it may increase bleeding risk and cause sun sensitivity, so use carefully. It's rated possibly unsafe in pregnancy and should be avoided while breastfeeding.

Chinese rhubarb root is well tolerated in food amounts but can cause cramping, diarrhea, nausea, and vomiting; chronic or excessive use may deplete potassium and harm the kidneys — avoid medicinal amounts in pregnancy and while nursing. Fo-ti may be unsafe; it's been linked to around 450 documented cases of liver injury in the medical literature, ranging from mild hepatitis to cirrhosis, at varying doses and durations.

It commonly causes abdominal pain, diarrhea, nausea, and vomiting (especially from unprocessed forms) and is rated possibly unsafe in both pregnancy and lactation. Hemp seed foods are generally well tolerated, but concentrated extracts and supplements are less studied; rare cases of anaphylaxis and allergy have been reported.

Side effects, ingredient by ingredient Dong Quai Rhubarb Fo-ti Hemp

Meds to double-check

Major interaction found
Known Interaction Concern · database check
Major identified

At least one ingredient has a documented Major-severity interaction. Check your medications for a personalized result.

Why this rating?
  • 4 of the 4 matched ingredients can interact with medications — Rhubarb, Fo-ti, Dong Quai, Hemp.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; diabetes medications; heart-rhythm medications.
  • For scale: 1,402 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before taking Tong Chang Pian Constipass, double-check with your doctor or pharmacist if you take blood thinners or antiplatelet drugs (Major risk with dong quai and fo-ti, Moderate with rhubarb, Minor with hemp). Also check if you use warfarin, digoxin, kidney or liver medications, diuretics, corticosteroids, stimulant laxatives, ACE inhibitors, antihypertensive drugs, or drugs metabolized by CYP2C8, CYP2B6, CYP1A2, or CYP3A4 enzymes.

No interactions are documented for the notopterygium or peach content, though we hold no data on these ingredients.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFormula with limited ingredient disclosure with insufficient evidence for its stated purpose. Major medication interactions have been identified, and safety information is well characterized.

This product brings together traditional herbs with overlapping properties, but it carries significant interaction risks — especially with blood thinners, heart medications, and kidney or liver drugs — and one ingredient (fo-ti) has a substantial safety history of liver damage. The evidence for its effectiveness at treating constipation or other conditions is not established.

If you take any prescription medications, particularly anticoagulants, digoxin, diuretics, or corticosteroids, check with your doctor or pharmacist before starting this product. Even if you don't take medications, discuss it with your healthcare provider to make sure it's right for you.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 4 of 6 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jul 18, 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

At a glance

General information

Key facts about Tong Chang Pian Constipass, straight from the product label.

Brand Guang Ci Tang
Barcode (UPC) 817967011990
Net contents 200 Tablet(s); 40 Gram(s)
Market status On market
Date entered into DSLD Jul 18, 2023
DSLD ID 288713
Product type Botanical
Supplement form Tablet Or Pill
Dietary claims / uses All Other
Intended target group(s) Adult (18 - 50 Years)
From the label
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 Tong Chang Pian Constipass by Guang Ci Tang, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
5 Tablet(s)
Maximum serving Sizes:
5 Tablet(s)
Servings per container
40
UPC/BARCODE
817967011990
IngredientAmount% DV
Proprietary Blend1000 mg--
Dong Quai0 NP--
Notopterygium0 NP--
Peach0 NP--
Chinese Rhubarb0 NP--
Fo-Ti, Cured0 NP--
Hemp0 NP--

Other ingredients: Corn Starch, Dextrin, Magnesium Stearate

Tap any ingredient to jump to its full detail below.

Label statements
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.
Formulation

5x concentrated

Blended before extraction.

No pharmaceuticals.

Heavy metals tested.

Product of China

FDA Statement of Identity

Herbal Dietary Supplement

General Statements

200mg

Formula

Minimal fillers.

Suggested/Recommended/Usage/Directions

Suggested Use: 5 tablets each time, 2 to 3 times a day, or consult a health care practitioner.

Precautions

Keep out of reach of children.

Seals/Symbols

GMP Certified

Is this label outdated? Report a formula or label change and our pharmacy team will review it.

See for yourself

Tong Chang Pian Constipass by Guang Ci Tang label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

Tong Chang Pian Constipass label

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)
What’s inside

The Ingredients in Tong Chang Pian Constipass by Guang Ci Tang

These are the 6 active ingredients this product is made of. Select any to open its full monograph.

Serving size5 Tablet(s) Dosage formTablet Or Pill Servings per container40 Amounts shown are per serving.

Most supplement products combine several ingredients, and a medication can interact with the product through any one of them. Each ingredient below shows whether it has known drug interactions.

Proprietary Blend

1000 mg per serving

Other (inactive) ingredients: Corn Starch, Dextrin, Magnesium Stearate. These complete the product’s ingredient list but are not active constituents.

Interaction report

Tong Chang Pian Constipass by Guang Ci Tang Drug Interactions

Want to check YOUR meds against Tong Chang Pian Constipass?

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 checker
1,401Drugs
2 Major 1,359 Moderate 40 Minor

Ingredients driving the most interactions

Fo-Ti, Cured 1,257
Hemp 938
Chinese Rhubarb 658
Dong Quai 163

Individual Drug Interactions

The ingredients in Tong Chang Pian Constipass interact with 1,401 drugs. Click any drug to see the details.

4 of the 6 ingredients in Tong Chang Pian Constipass interact with drugs. Each result below shows which ingredient is responsible. Fo-Ti, Cured Hemp Chinese Rhubarb Dong Quai

Each ingredient & the kinds of drugs it affects

For each ingredient in Tong Chang Pian Constipass with known interactions, here are the types of medications they can affect. Open any type for the detail — or search your exact drug in the checker above.

Fo-Ti, Cured17 drug types · 1,257 drugs

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.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, fo-ti might increase the risk of hypoglycemia when taken with antidiabetes drugs.
Fo-ti reportedly has hypoglycemic effects.

Likelihood Possible Evidence D
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.

Likelihood Probable Evidence D
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.

Likelihood Possible Evidence D
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.

Likelihood Possible Evidence D
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.

Likelihood Possible Evidence D
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.

Likelihood Possible Evidence D
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.

Likelihood Possible Evidence D
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.

Likelihood Possible Evidence D
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.

Likelihood Possible Evidence D
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.

Likelihood Possible Evidence D
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.

Likelihood Possible Evidence D
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.

Likelihood Probable Evidence D
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.

Likelihood Possible Evidence D
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.

Likelihood Possible Evidence D
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.

Likelihood Possible Evidence D
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.

Likelihood Possible Evidence D
Fo-Ti, Cured full monograph & interactions

Hemp6 drug types · 938 drugs

Estrogens

Theoretically, hemp might interfere with hormone therapy due to its estrogenic effects.
In an ovariectomized animal model, a diet containing hemp seed 1%, 2%, or 10% resulted in normalized plasma levels of 17-beta-estradiol. The mechanism of action for this effect is unclear.

Likelihood Possible Evidence D
Ace Inhibitors (Aceis)

Theoretically, consuming hemp seed protein isolate with ACE inhibitors might have additive effects and increase the risk of hypotension.
Hemp seed protein hydrolysate has shown ACE inhibitor-like effects in a hypertensive animal model. However, hempseed oil consumption does not seem to reduce blood pressure in humans. Until more is known, monitor blood pressure and potassium levels.

Likelihood Unlikely Evidence D
Anticoagulant/Antiplatelet Drugs

Theoretically, hemp seed might increase the risk of bleeding when used concomitantly with anticoagulant/antiplatelet drugs.
In animal research, hemp seed at 5% of the diet inhibits platelet aggregation in vitro. However, in human research, taking hemp seed oil 2 grams daily for 12 weeks does not inhibit the aggregation of platelets in vitro.

Likelihood Possible Evidence D
Antihypertensive Drugs

Theoretically, hemp seed protein may have additive effects with antihypertensive drugs.
In a hypertensive animal model, hemp seed protein hydrolysate reduced systolic blood pressure by a mechanism possibly involving the inhibition of renin and angiotensin converting enzyme (ACE) activities. However, there was no effect of hemp seed protein on blood pressure in normotensive animals. Furthermore, hempseed oil consumption does not seem to reduce blood pressure in humans.

Likelihood Unlikely Evidence D
Cytochrome P450 1A2 (Cyp1A2) Substrates

Theoretically, hemp might decrease the levels and clinical effects of CYP1A2 substrates.
In vitro research shows that hemp induces CYP1A2 enzymes.

Likelihood Possible Evidence D
Cytochrome P450 3A4 (Cyp3A4) Substrates

Theoretically, hemp might decrease the levels and clinical effects of CYP3A4 substrates.
In vitro research shows that hemp induces CYP3A4 enzymes.

Likelihood Possible Evidence D
Hemp full monograph & interactions

Chinese Rhubarb8 drug types · 658 drugs

Corticosteroids

Theoretically, frequent and high doses of rhubarb might increase the risk of hypokalemia when taken with corticosteroids.
Rhubarb has stimulant laxative effects. Overuse of rhubarb might compound corticosteroid-induced potassium loss.

Likelihood Possible Evidence D
Cyclosporine (Neoral, Sandimmune)

Theoretically, taking rhubarb with cyclosporine might reduce cyclosporine levels.
Animal research shows that co-administration of rhubarb decoction 0.25 or 1 gram/kg with cyclosporine 2.5 mg/kg, decreases cyclosporine maximum plasma concentration and overall exposure levels when compared with taking cyclosporine alone. The authors theorize that rhubarb might reduce cyclosporine bioavailability by inducing of P-glycoprotein and/or cytochrome P450 3A4. However, since rhubarb was administered as a single oral dose and enzyme induction usually occurs after multiple doses, it is possible that cyclosporine absorption was actually reduced via rhubarb's stimulant laxative effects. Also, the composition of the rhubarb decoction was not described.

Likelihood Possible Evidence D
Digoxin (Lanoxin)

Theoretically, overuse of rhubarb might increase the risk of adverse effects when taken with digoxin.
Rhubarb has stimulant laxative effects. Overuse of rhubarb might cause potassium depletion, increasing the risk of digoxin toxicity.

Likelihood Possible Evidence D
Diuretic Drugs

Theoretically, frequent and high doses of rhubarb might increase the risk of hypokalemia.
Rhubarb has stimulant laxative effects. Overuse of rhubarb might cause potassium depletion and compound diuretic-induced potassium loss.

Likelihood Possible Evidence D
Hepatotoxic Drugs

Theoretically, concomitant use of rhubarb with potentially hepatotoxic drugs might increase the risk of developing liver damage.
Some animal research suggests that anthraquinones in rhubarb might have hepatotoxic effects. Also, rhubarb use has been linked to at least 24 cases of liver injury, although details on the dose of rhubarb and duration of use in these cases is unclear.

Likelihood Possible Evidence D
Nephrotoxic Drugs

Theoretically, long-term use of anthraquinones from rhubarb might increase the risk of nephrotoxicity when used with nephrotoxic drugs.
The anthraquinone constituents of rhubarb have been shown to induce nephrotoxicity in animal research. Additionally, in a case report, a 23-year old female presented with kidney failure after taking 6 tablets of a proprietary slimming agent (found to contain the anthraquinones emodin and aloe-emodin from rhubarb) daily for 6 weeks and then adding diclofenac 25 mg 4 times daily for 2 days. The authors postulate that the anthraquinone constituents of rhubarb contributed to the renal dysfunction, and the addition of diclofenac, a nephrotoxic drug, led to renal failure. Until more is known, advise patients to avoid taking rhubarb if they are taking other potentially nephrotoxic drugs.

Likelihood Possible Evidence D
Stimulant Laxatives

Theoretically, rhubarb might increase the risk for fluid and electrolyte loss when taken with other stimulant laxatives.
Rhubarb has stimulant laxative effects. Concomitant use with stimulant laxatives might compound fluid and electrolyte loss.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Theoretically, excessive use of rhubarb might increase the risk of bleeding when taken with warfarin.
Rhubarb has stimulant laxative effects and can cause diarrhea. Diarrhea can increase the effects of warfarin, increase international normalized ratio (INR), and increase the risk of bleeding. Advise patients who take warfarin not to take excessive amounts of rhubarb.

Likelihood Possible Evidence D
Chinese Rhubarb full monograph & interactions

Dong Quai3 drug types · 163 drugs

Warfarin (Coumadin)

Dong quai may increase the risk of bleeding when used with warfarin.
Case reports suggest that concomitant use of dong quai with warfarin can increase the anticoagulant effects of warfarin and increase the risk of bleeding. In one case, after 4 weeks of taking dong quai 565 mg once or twice daily, the international normalized ratio (INR) increased to 4.9. The INR normalized 4 weeks after discontinuation of dong quai.

Likelihood Probable Evidence D
Anticoagulant/Antiplatelet Drugs

Theoretically, dong quai may increase the risk of bleeding when used with anticoagulant or antiplatelet drugs; however, research is conflicting.
Animal studies suggest that dong quai has antithrombin activity and inhibits platelet aggregation due to its coumarin components. Additionally, some case reports in humans suggest that dong quai can increase the anticoagulant effects of warfarin. However, clinical research in healthy adults shows that taking 1 gram of dong quai root daily for 3 weeks does not significantly inhibit platelet aggregation or cause bleeding. Until more is known, use dong quai with caution in patients taking antiplatelet/anticoagulant drugs.

Likelihood Possible Evidence D
Estrogens

Theoretically, dong quai may reduce the effects of estrogens.
Dong quai has estrogenic effects. Theoretically, concomitant use of large amounts of dong quai might interfere with hormone replacement therapy due to competition for estrogen receptors.

Likelihood Possible Evidence D
Dong Quai full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Tong Chang Pian Constipass, from the product label.

Guang Ci Tang

See all Guang Ci Tang products
Name
ActiveHerb Technology, Inc.
City
San Diego
State
CA
ZipCode
92121
Phone Number
(888)805-4372
Pharmacist Counseling Corner

Tong Chang Pian Constipass by Guang Ci Tang: Common Questions

Does Tong Chang Pian Constipass by Guang Ci Tang interact with any medications?
Yes. Based on its ingredients, Tong Chang Pian Constipass has a known interaction with 1,401 medications, including 2 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Tong Chang Pian Constipass contains 6 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Is it safe to take Tong Chang Pian Constipass while pregnant?
No. Dong quai and Chinese rhubarb (medicinal amounts) are rated possibly unsafe in pregnancy because they may stimulate the uterus and affect bleeding. Fo-ti is also rated possibly unsafe. Avoid this product if you're pregnant or planning to become pregnant — talk with your doctor or pharmacist first.
What's the most serious interaction this product has?
Dong quai combined with warfarin (Coumadin) is a Major interaction — it can significantly increase warfarin's blood-thinning effect and raise your bleeding risk. If you take warfarin, check with your doctor or pharmacist before taking this product.
Can I take this if I have liver or kidney problems?
You should check with your doctor first. Fo-ti has been linked to liver injury in around 450 documented cases, and Chinese rhubarb can potentially harm the kidneys, especially with long-term use. Your healthcare provider can assess whether this product is safe for your situation.
What are the most common side effects?
Dong quai most commonly causes burping and flatulence. Chinese rhubarb can cause cramps, diarrhea, nausea, and vomiting. Unprocessed fo-ti often causes abdominal pain, diarrhea, nausea, and vomiting. These are generally mild but can be bothersome.
Does this product actually work for constipation?
The evidence isn't established in our data. We have no reliable evidence that the ingredients in this product treat constipation. Before relying on it, ask your doctor or pharmacist whether it's appropriate for your situation.
Is it safe to breastfeed while taking this product?
No. Dong quai is rated unsafe while breastfeeding, Chinese rhubarb may pass laxative compounds into breast milk, and fo-ti is rated possibly unsafe for lactation. Avoid this product if you're nursing — talk with your doctor or pharmacist about safe alternatives.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

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Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

Tong Chang Pian Constipass label
Go deeper

The Full Monographs Behind Tong Chang Pian Constipass’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Herb & supplement monograph

Dong Quai

Interacts with 163 drugs

Dong Quai is a traditional Chinese herb often called "female ginseng" and is mostly used for menstrual and menopausal complaints. High-quality scientific evidence that it works for these use...

Read the full Dong Quai monograph → Herb & supplement monograph

Rhubarb

Interacts with 658 drugs

Rhubarb root has a long history of use as a laxative and in traditional Chinese medicine, and its edible stalks are a common food. Most medicinal claims are backed by limited or low-quality...

Read the full Rhubarb monograph → Herb & supplement monograph

Fo-ti

Interacts with 1,257 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 benefits is limited, and processed Fo-ti h...

Read the full Fo-ti monograph → Herb & supplement monograph

Hemp

Interacts with 938 drugs

Hemp seeds and hemp seed oil are nutritious foods rich in protein, fiber, and healthy omega-3 and omega-6 fatty acids, and they are generally safe for most people as part of the diet. While...

Read the full Hemp monograph →
Sources

Sources & How We Checked

Tong Chang Pian Constipass'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.

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 79 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.

Dong Quai 19 references
  1. Hirata JD, Swiersz LM, Zell B, et al. Does dong quai have estrogenic effects in postmenopausal women? A double-blind, placebo-controlled trial. Fertil Steril 1997;68:981-6. PubMed
  2. Page RL II, Lawrence JD. Potentiation of warfarin by dong quai. Pharmacotherapy 1999;19:870-6. PubMed
  3. Heck AM, DeWitt BA, Lukes AL. Potential interactions between alternative therapies and warfarin. Am J Health Syst Pharm 2000;57:1221-7. DOI
  4. Eagon PK, Elm MS, Hunter DS, et al. Medicinal herbs: modulation of estrogen action. Era of Hope Mtg, Dept Defense; Breast Cancer Res Prog, Atlanta, GA 2000;Jun 8-11.
  5. Dr. Duke's Phytochemical and Ethnobotanical Databases. Available at: http://www.ars-grin.gov/duke/.
  6. Amato P, Christophe S, Mellon PL. Estrogenic activity of herbs commonly used as remedies for menopausal symptoms. Menopause 2002;9:145-50. PubMed
  7. Shi M, Chang L, He G. [Stimulating action of Carthamus tinctorius L., Angelica sinensis (Oliv.) Diels and Leonurus sibiricus L. on the uterus]. Zhongguo Zhong Yao Za Zhi 1995;20:173-5, 192.
  8. Hoult JR, Paya M. Pharmacological and biochemical actions of simple coumarins: natural products with therapeutic potential. Gen Pharmacol 1996;27:713-22.. PubMed
  9. Cheong JL, Bucknall R. Retinal vein thrombosis associated with a herbal phytoestrogen preparation in a susceptible patient. Postgrad Med J 2005;81:266-7.. PubMed
  10. Chang CJ, Chiu JH, Tseng LM, et al. Modulation of HER2 expression by ferulic acid on human breast cancer MCF7 cells. Eur J Clin Invest 2006;36:588-96. PubMed
  11. Chuang CH, Doyle P, Wang JD, et al. Herbal medicines used during the first trimester and major congenital malformations: an analysis of data from a pregnancy cohort study. Drug Saf 2006;29:537-48. PubMed
  12. Lau CBS, Ho TCY, Chan TWL, Kim SCF. Use of dong quai (Angelica sinensis) to treat peri- and postmenopausal symptoms in women with breast cancer: is it appropriate? Menopause 2005;12:734-40.
  13. Ellis GR, Stephens MR. Untitled (photograph and a brief case report). BMJ 1999;319:650.
  14. Nambiar, S., Schwartz, R. H., and Constantino, A. Hypertension in mother and baby linked to ingestion of Chinese herbal medicine. West J Med 1999;171(3):152.
  15. Lee, S. K., Cho, H. K., Cho, S. H., Kim, S. S., Nahm, D. H., and Park, H. S. Occupational asthma and rhinitis caused by multiple herbal agents in a pharmacist. Ann.Allergy Asthma Immunol. 2001;86(4):469-474. PubMed
  16. Xu, J. and Li, G. [Observation on short-term effects of Angelica injection on chronic obstructive pulmonary disease patients with pulmonary hypertension]. Zhongguo Zhong Xi Yi Jie He Za Zhi 2000;20(3):187-189.
  17. Scott, G. N. and Elmer, G. W. Update on natural product--drug interactions. Am J Health Syst.Pharm 2-15-2002;59(4):339-347. PubMed
  18. Circosta, C., Pasquale, R. D., Palumbo, D. R., Samperi, S., and Occhiuto, F. Estrogenic activity of standardized extract of Angelica sinensis. Phytother.Res. 2006;20(8):665-669.
  19. Fung FY, Wong WH, Ang SK, et al. A randomized, double-blind, placebo- controlled study on the anti-haemostatic effects of Curcuma longa, Angelica sinensis and Panax ginseng. Phytomedicine. 2017;32:88-96. PubMed

See these in context on the Dong Quai monograph →

Rhubarb 20 references
  1. Blumenthal M, ed. The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. Trans. S. Klein. Boston, MA: American Botanical Council, 1998.
  2. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
  3. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
  4. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  5. Nusko G, Schneider B, Schneider I, et al. Anthranoid laxative use is not a risk factor for colorectal neoplasia: results of a prospective case control study. Gut 2000;46:651-5. PubMed
  6. Kwan TH, Tong MK, Leung KT, et al. Acute renal failure associated with prolonged intake of slimming pills containing anthraquinones. Hong Kong Med J 2006;12:394-7.
  7. Fairbairn JW. The anthraquinone laxatives. Biological assay and its relation to chemical structure. Pharmacology 1976;14:48-61. PubMed
  8. Siegers, C. P., Hertzberg-Lottin, E., Otte, M., and Schneider, B. Anthranoid laxative abuse--a risk for colorectal cancer? Gut 1993;34(8):1099-1101. PubMed
  9. Fan, J. G. Evaluating the efficacy and safety of Danning Pian in the short-term treatment of patients with non-alcoholic fatty liver disease: a multicenter clinical trial. Hepatobiliary.Pancreat.Dis.Int 2004;3(3):375-380.
  10. Yan, M., Zhang, L. Y., Sun, L. X., Jiang, Z. Z., and Xiao, X. H. Nephrotoxicity study of total rhubarb anthraquinones on Sprague Dawley rats using DNA microarrays. J Ethnopharmacol. 4-15-2006; PubMed
  11. Zhang, J. H., Li, L. S., and Zhang, M. Clinical effects of rheum and captopril on preventing progression of chronic renal failure. Chin Med J (Engl.) 1990;103(10):788-793.
  12. Mitsuma, T., Yokozawa, T., Oura, H., and Terasawa, K. [Rhubarb therapy in patients with chronic renal failure (Part 2)]. Nippon Jinzo Gakkai Shi 1987;29(2):195-207.
  13. Wu, C. X. [A preliminary study on the effect of a single Rheum officinale in heavy doses in the treatment of acute icteric hepatitis]. Zhong.Xi.Yi.Jie.He.Za Zhi.(Chinese Journal of Modern Developments in Traditional Medicine) 1984;4(2):88-89.
  14. Jiao, D. H. [Clinical research on the hemostatic effect of rhubarb on peptic ulcer with acute bleeding]. Zhong.Xi.Yi.Jie.He.Za Zhi.(Chinese Journal of Modern Developments in Traditional Medicine) 1984;4(10):597-600, 579.
  15. Jiao, D. H., Ma, Y. H., Chen, S. J., Liu, C. T., Shu, H. N., and Chu, C. M. Resume of 400 cases of acute upper digestive tract bleeding treated by rhubarb alone. Pharmacology 1980;20 Suppl 1:128-130.
  16. Zhang, JH, Yao, XD, Song, Y, and et al. [Long-term treating effects of rhubarb and captopril in delaying the progression of renal failure]. Chinese Kidney Disease Journal 1993;9(4):197-201.
  17. Rehman H, Begum W, Anjum F, Tabasum H, Zahid S. Effect of rhubarb (Rheum emodi) in primary dysmenorrhoea: a single-blind randomized controlled trial. J Complement Integr Med. 2015 Mar;12(1):61-9.
  18. Yu CP, Lin HJ, Lin SP, Shia CS, Chang PH, Hou YC, Hsieh YW. Rhubarb decreased the systemic exposure of cyclosporine, a probe substrate of P-glycoprotein and CYP 3A. Xenobiotica. 2016 Aug;46(8):677-82. PubMed
  19. Byeon JH, Kil JH, Ahn YC, Son CG. Systematic review of published data on herb induced liver injury. J Ethnopharmacol 2019;233:190-6. PubMed
  20. Zhao D, Feng SX, Zhang HJ, et al. Pharmacokinetics, tissue distribution and excretion of five rhubarb anthraquinones in rats after oral administration of effective fraction of anthraquinones from rheum officinale. Xenobiotica. 2021;51(8):916-925. PubMed

See these in context on the Rhubarb monograph →

Fo-ti 28 references
  1. 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.
  2. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
  3. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  4. Covington TR, et al. Handbook of Nonprescription Drugs. 11th ed. Washington, DC: American Pharmaceutical Association, 1996.
  5. 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.
  6. 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.
  7. 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
  8. 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
  9. 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
  10. 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
  11. 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.
  12. 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
  13. 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
  14. 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
  15. 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
  16. 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
  17. 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
  18. 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.
  19. 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
  20. 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
  21. McGuffin, M., Hobbs, C., Upton, R., and Goldberg, A. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC;1997.
  22. 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
  23. 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.
  24. 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
  25. 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
  26. 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
  27. 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.
  28. 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

See these in context on the Fo-ti monograph →

Hemp 12 references
  1. Kaul N, Kreml R, Austria JA, et al. A comparison of fish oil, flaxseed oil and hempseed oil supplementation on selected parameters of cardiovascular health in healthy volunteers. J Am Coll Nutr 2008;27:51-8. PubMed
  2. Saberivand A, Karimi I, Becker LA, et al. The effects of Cannabis sativa L. seed (hempseed) in the ovariectomized rat model of menopause. Methods Find Exp Clin Pharmacol. 2010;32(7):467-73. PubMed
  3. Girgih AT, Alashi A, He R, Malomo S, Aluko RE. Preventive and treatment effects of a hemp seed (Cannabis sativa L.) meal protein hydrolysate against high blood pressure in spontaneously hypertensive rats. Eur J Nutr. 2014;53(5):1237-46. PubMed
  4. Richard MN, Ganguly R, Steigerwald SN, Al-Khalifa A, Pierce GN. Dietary hempseed reduces platelet aggregation. J Thromb Haemost. 2007;5(2):424-5. PubMed
  5. Stadtmauer G, Beyer K, Bardina L, Sicherer SH. Anaphylaxis to ingestion of hempseed (Cannabis sativa). J Allergy Clin Immunol. 2003;112(1):216-7. PubMed
  6. Del Bo' C, Deon V, Abello F, et al. Eight-week hempseed oil intervention improves the fatty acid composition of erythrocyte phospholipids and the omega-3 index, but does not affect the lipid profile in children and adolescents with primary hyperlipidemia. PubMed
  7. Alkhammash S, Tsui H, Thomson DMP. Cannabis and hemp seed allergy. J Allergy Clin Immunol Pract. 2019;7(7):2429-2430.e1. PubMed
  8. Stokes JR, Hartel R, Ford LB, Casale TB. Cannabis (hemp) positive skin tests and respiratory symptoms. Ann Allergy Asthma Immunol. 2000;85(3):238-40. PubMed
  9. Déléaval M, Burri H, Bakelants E. Harmless herbs? A case report of acquired long QT syndrome and torsades de pointes in a patient taking herbal supplements. HeartRhythm Case Rep 2022;8(5):309-12. PubMed
  10. Singh M, Sehgal M, Yacoub M, et al. Severe liver dysfunction in a toddler receiving nonprescription phytocannabinoid. J Am Pharm Assoc (2003) 2022;62(4):1438-1440. PubMed
  11. Clark E, Nilsson U, Samaran Q, Raison-Peyron N. Allergic contact dermatitis from Cannabis sativa (hemp) seed oil. Contact Dermatitis 2022;87(3):292-293.
  12. Haron MH, Dale O, Martin K, et al. Evaluation of the Herb-Drug Interaction Potential of Commonly Used Botanicals on the US Market with Regard to PXR- and AhR-Mediated Influences on CYP3A4 and CYP1A2. J Diet Suppl 2022. PubMed

See these in context on the Hemp monograph →

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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

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