Interactions on record — worth a quick check against your medications. Based on 6 of 7 ingredients. Check your meds →
Dietary supplement

Collinsonia Formula Ingredients & Drug Interactions

by Genestra Brands

Collinsonia Formula label
See full label image
Capsule Category: Botanical
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 9, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Collinsonia Formula 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: Moderate

Collinsonia Formula is a dietary supplement by Genestra Brands with 7 active ingredients. Its ingredients are commonly taken for cough and sore throat, dry mouth and throat irritation, digestive upset and heartburn.Based on those ingredients, 2,162 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are organic Marshmallow, Milk Thistle (Silybum marianum) seed std. extract, organic Dandelion. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Collinsonia Formula by Genestra Brands

Ask about any prescription or over-the-counter medication and we check it for interactions with Collinsonia Formula by Genestra Brands — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Collinsonia Formula by Genestra Brands

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 Jul 12, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 7 of its 7 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

Collinsonia Formula has 7 active ingredients: organic marshmallow, parsley, stoneroot, organic calendula, organic dandelion, organic witch hazel, and milk thistle seed extract (standardized). Together they're designed to support circulation and venous health, with marshmallow and calendula contributing demulcent (soothing) and wound-healing properties, while witch hazel and dandelion are traditionally used to tone and support vascular function.

The product also contains hypromellose, an inactive ingredient used in the capsule.

Does it work?

Moderate 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

This product doesn't appear to be marketed for a specific use, so we graded its ingredients' overall clinical evidence instead.

Moderate

Some clinical evidence supports its ingredients for:

Why this rating?
  • We looked at the product name, claims, and label statements and couldn't find a stated purpose to grade.
  • Since the label doesn't commit to one use, we graded the ingredients' overall clinical evidence instead.
  • On file: Diabetes — rated "Possibly Effective" (Milk Thistle) (Natural Medicines).
  • On file: Hemorrhoids — rated "Possibly Effective" (Witch Hazel) (Natural Medicines).

The evidence for what these ingredients do isn't well established in the data we hold. Marshmallow, parsley, stoneroot, calendula, and dandelion all show insufficient reliable evidence to rate for their listed uses.

Witch hazel is possibly effective for hemorrhoids but possibly ineffective for eczema. Milk thistle is possibly effective for diabetes, though it's not marketed as a diabetes product here.

If you're considering this product for a specific condition, ask your pharmacist what the research actually supports.

The evidence, ingredient by ingredient Marshmallow Parsley Calendula Dandelion Witch Hazel Milk Thistle

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 5 of the 6 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 6 of 6.
  • General safety write-ups exist for 6 of 6.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Marshmallow is generally well tolerated for short-term use, though human safety data are limited. It should be avoided during pregnancy and breastfeeding.

Parsley is safe in food amounts but concentrated supplements may not be—large doses carry rare serious risks including hemolytic anemia and kidney damage, and it should be avoided in medicinal amounts during pregnancy. Calendula is generally well tolerated on the skin but can trigger allergic reactions; oral use during pregnancy is best avoided.

Dandelion is well tolerated as food but supplement doses are less studied; most common side effects are diarrhea, heartburn, and stomach discomfort. Witch hazel is generally well tolerated topically but isn't meant to be taken by mouth; oral use at high doses may damage the kidneys or liver.

Milk thistle is generally well tolerated, though it should be avoided during pregnancy and used cautiously while breastfeeding.

Side effects, ingredient by ingredient Marshmallow Parsley Calendula Dandelion Witch Hazel Milk Thistle

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 5 of the 6 matched ingredients can interact with medications — Milk Thistle, Calendula, Dandelion, Marshmallow, Parsley.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; diabetes medications; lithium.
  • For scale: 2,163 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 you take this, double-check any blood thinners (including warfarin and antiplatelet drugs like aspirin), diabetes medications, water pills (especially potassium-sparing diuretics), lithium, medications broken down by the liver enzyme CYP1A2 (parsley and dandelion), fluoroquinolone antibiotics like ciprofloxacin (dandelion), certain hepatitis C drugs like sofosbuvir and ledipasvir (milk thistle), morphine, and sedating medications (CNS depressants). The severity of these interactions ranges from Moderate to Minor, with Moderate interactions being most serious.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with some supporting evidence behind its ingredients' uses. Moderate medication interactions have been identified, and safety information is well characterized.

This product combines traditional vein-support herbs but carries meaningful interactions with blood thinners, diabetes drugs, water pills, and several others. If you take any regular medications—especially warfarin, lithium, antidiabetes drugs, or antibiotics—check your list below before starting.

Pregnant or breastfeeding people should talk with their doctor or pharmacist first.

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

Assessment coverage: 6 of 7 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jan 22, 2021.

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 Collinsonia Formula, straight from the product label.

Brand Genestra Brands
Barcode (UPC) 883196111800
Net contents 90 Vegetarian Capsule(s)
Market status On market
Date entered into DSLD Jan 22, 2021
DSLD ID 241137
Product type Botanical
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Women (not pregnant or lactating)
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 Collinsonia Formula by Genestra Brands, 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:
2 Capsule(s)
Maximum serving Sizes:
2 Capsule(s)
Servings per container
45
UPC/BARCODE
883196111800
IngredientAmount% DV
organic Marshmallow200 mg--
Parsley80 mg--
Stoneroot200 mg--
Organic Calendula200 mg--
organic Dandelion150 mg--
Organic Witch Hazel80 mg--
Milk Thistle (Silybum marianum) seed std. extract200 mg--

Other ingredients: Hypromellose

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.
Suggested/Recommended/Usage/Directions

Recommended Dose: Take 2 capsules 2 times daily with meals, a few hours before or after taking medications, minerals or B-vitamin supplements, or as recommended by your health professional.

Precautions

Warning: If you are pregnant, lactating or allergic to plants of the Asteraceae/Compositae/Daisy family, have heart disease, high or low blood pressure, diabetes, liver, kidney or gall bladder disorders, bowel obstruction or edema, or taking products containing diuretics, do not use. If you are taking any medication or have any health condition, consult your health professional before use.

Warning: If you are pregnant, lactating or allergic to plants of the Asteraceae/Compositae/Daisy family, have heart disease, high or low blood pressure, diabetes, liver, kidney or gall bladder disorders, bowel obstruction or edema, or taking products containing diuretics, do not use.

If you experience dizziness, confusion, muscle weakness or pain, abnormal heartbeat or difficulty breathing, stop use and seek medical attention immediately. If you develop symptoms of liver trouble or allergy, stop use. Some people may experience gastric irritation.

Keep out of the reach of children.

Use only if safety seal is intact.

Storage

Store in a cool, dry place.

FDA Disclaimer Statement

This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

General Statements

Contents may not fill package in order to accommodate required labeling. Please rely on stated quantity. Scan to learn about our quality excellence

FDA Statement of Identity

Dietary Supplement

Formulation

Traditional support for healthy gastrointestinal function

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

See for yourself

Collinsonia Formula by Genestra Brands label

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

Collinsonia Formula 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 Collinsonia Formula by Genestra Brands

These are the 7 active ingredients this product is made of. Select any to open its full monograph.

Serving size2 Capsule(s) Dosage formCapsule Servings per container45 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.

Organic Marshmallow

Interacts with
2,040 drugs
200 mg per serving

Marshmallow root is a traditional herb rich in soothing, gel-like fibers called mucilage, which is why it has long been used for coughs, sore throats,...

Organic Marshmallow monograph & interactions

Parsley

Interacts with
443 drugs
80 mg per serving

Parsley is a popular culinary herb that is safe to eat in normal food amounts and is a good source of vitamins K and C. It is traditionally used as a...

Parsley monograph & interactions

Stoneroot

200 mg per serving

Organic Calendula

Interacts with
248 drugs
200 mg per serving

Calendula is a flowering plant whose petals are used mainly in skin creams, oils, and ointments to soothe minor irritation and support wound healing....

Organic Calendula monograph & interactions

Organic Dandelion

Interacts with
457 drugs
150 mg per serving

Dandelion is a common plant used in food and traditional medicine, often promoted as a natural 'water pill' and digestive aid. Human evidence for thes...

Organic Dandelion monograph & interactions

Organic Witch Hazel

No known
interactions
80 mg per serving

Witch hazel is a plant-based astringent used mostly on the skin for minor irritation, hemorrhoids, and oily skin. It is generally well tolerated as a...

Organic Witch Hazel monograph & interactions

Milk Thistle (Silybum marianum) seed std. extract

Interacts with
954 drugs
200 mg per serving Form: Silymarin

Milk thistle is a popular herbal supplement most often used for liver health, and its main active component is a group of compounds called silymarin....

Milk Thistle (Silybum marianum) seed std. extract monograph & interactions

Other (inactive) ingredients: Hypromellose. These complete the product’s ingredient list but are not active constituents.

Interaction report

Collinsonia Formula by Genestra Brands Drug Interactions

Want to check YOUR meds against Collinsonia Formula?

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
2,162Drugs
561 Moderate 1,601 Minor

Ingredients driving the most interactions

organic Marshmallow 2,040
Milk Thistle (Silybum marianum) seed std. extract 954
organic Dandelion 457
Parsley 443
Organic Calendula 248

Individual Drug Interactions

The ingredients in Collinsonia Formula interact with 2,162 drugs. Click any drug to see the details.

5 of the 7 ingredients in Collinsonia Formula interact with drugs. Each result below shows which ingredient is responsible. organic Marshmallow Milk Thistle (Silybum marianum) seed std. extract organic Dandelion Parsley Organic Calendula

Each ingredient & the kinds of drugs it affects

For each ingredient in Collinsonia Formula 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.

organic Marshmallow3 drug types · 2,040 drugs

Lithium

Theoretically, due to potential diuretic effects, marshmallow might reduce excretion and increase levels of lithium.
Marshmallow is thought to have diuretic properties. To avoid lithium toxicity, the dose of lithium might need to be decreased when used with marshmallow.

Likelihood Probable Evidence D
Anticoagulant/Antiplatelet Drugs

Theoretically, marshmallow flower might have antiplatelet effects.
Animal research suggests that marshmallow flower extract has antiplatelet effects. However, the root and leaf of marshmallow, not the flower, are the plant parts most commonly found in dietary supplements. Theoretically, use of marshmallow flower with anticoagulant/antiplatelet drugs can have additive effects, and might increase the risk for bleeding in some patients.

Likelihood Unlikely Evidence D
Oral Drugs

Theoretically, mucilage in marshmallow might impair absorption of oral drugs.
Marshmallow contains mucilage which can affect oral drug absorption. To avoid changes in absorption, take marshmallow 30-60 minutes after oral medications.

Likelihood Possible Evidence D
organic Marshmallow full monograph & interactions

Milk Thistle (Silybum marianum) seed std. extract17 drug types · 954 drugs

Antidiabetes Drugs

Taking milk thistle with antidiabetes drugs may increase the risk of hypoglycemia.
Clinical research shows that milk thistle extract, alone or along with tree turmeric extract, can lower blood glucose levels and glycated hemoglobin (HbA1c) in patients with type 2 diabetes, including those already taking antidiabetes drugs. Additionally, animal research shows that milk thistle extract increases the metformin maximum plasma concentration and area under the curve and decreases the renal clearance of metformin, due to inhibition of the multi-drug and toxin extrusion protein 1 (MATE1) renal tubular transport protein.

Likelihood Possible Evidence B
Cytochrome P450 2B6 (Cyp2B6) Substrates

Theoretically, milk thistle might inhibit CYP2B6.
An in vitro study shows that silybin, a constituent of milk thistle, binds to and noncompetitively inhibits CYP2B6. Additionally, silybin might downregulate the expression of CYP2B6 by decreasing mRNA and protein levels.

Likelihood Possible Evidence D
Glucuronidated Drugs

Theoretically, milk thistle might affect the clearance of drugs that undergo glucuronidation.
Laboratory research shows that milk thistle constituents inhibit uridine diphosphoglucuronosyl transferase (UGT), the major phase 2 enzyme that is responsible for glucuronidation. Theoretically, this could decrease the clearance and increase levels of glucuronidated drugs. Other laboratory research suggests that a milk thistle extract of silymarin might inhibit beta-glucuronidase, although the significance of this effect is unclear.

Likelihood Possible Evidence D
Ledipasvir

Theoretically, milk thistle might increase the levels and clinical effects of ledipasvir.
Animal research in rats shows that milk thistle increases the area under the curve (AUC) for ledipasvir and slows its elimination.

Likelihood Possible Evidence D
Morphine

Theoretically, concomitant use of milk thistle with morphine might affect serum levels of morphine and either increase or decrease its effects.
Animal research shows that milk thistle reduces serum levels of morphine by up to 66%. In contrast, laboratory research shows that milk thistle constituents inhibit uridine diphosphoglucuronosyl transferase (UGT), the major phase 2 enzyme that is responsible for glucuronidation. Theoretically, this could decrease the clearance and increase morphine levels. The effect of taking milk thistle on morphine metabolism in humans is not known.

Likelihood Possible Evidence D
Raloxifene (Evista)

Theoretically, milk thistle might decrease the clearance and increase levels of raloxifene.
Laboratory research suggests that the milk thistle constituents silibinin and silymarin inhibit the glucuronidation of raloxifene in the intestines.

Likelihood Possible Evidence D
Sirolimus (Rapamune)

Milk thistle might decrease the clearance of sirolimus.
Pharmacokinetic research shows that a milk thistle extract of silymarin decreases the apparent clearance of sirolimus in hepatically impaired renal transplant patients. It is unclear if this interaction occurs in patients without hepatic impairment.

Likelihood Possible Evidence B
Sofosbuvir (Solvaldi)

Theoretically, milk thistle might decrease the levels and clinical effects of sofosbuvir.
Animal research in rats shows that milk thistle reduces the metabolism of sofosbuvir, as well as the hepatic uptake of its active metabolite.

Likelihood Possible Evidence D
Tamoxifen (Nolvadex)

Theoretically, the milk thistle constituent silibinin might increase tamoxifen levels and interfere with its conversion to an active metabolite.
Animal research suggests that the milk thistle constituent silibinin might increase plasma levels of tamoxifen and alter its conversion to an active metabolite. The mechanism appears to involve inhibition of pre-systemic metabolism of tamoxifen by cytochrome P450 (CYP) 2C9 and CYP3A4, and inhibition of P-glycoprotein-mediated efflux of tamoxifen into the intestine for excretion. Whether this interaction occurs in humans is not known.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Theoretically, milk thistle might increase the effects of warfarin.
In one case report, a man stabilized on warfarin experienced an increase in INR from 2.64 to 4.12 after taking a combination product containing milk thistle 200 mg daily, as well as dandelion, wild yam, niacinamide, and vitamin B12. Levels returned to normal after stopping the supplement. Although a direct correlation between milk thistle and the change in INR cannot be confirmed, some in vitro research suggests that milk thistle might inhibit cytochrome P450 2C9 (CYP2C9), an enzyme involved in the metabolism of various drugs, including warfarin.

Likelihood Possible Evidence D
Cytochrome P450 2C9 (Cyp2C9) Substrates

It is unclear if milk thistle inhibits CYP2C9; research is conflicting.
In vitro research suggests that milk thistle might inhibit CYP2C9. Additionally, 3 case reports from the World Health Organization (WHO) adverse drug reaction database describe increased toxicity in patients taking milk thistle and cancer medications that are CYP2C9 substrates, including imatinib and capecitabine. However, contradictory clinical research shows that milk thistle extract does not inhibit CYP2C9 or significantly affect levels of the CYP2C9 substrate tolbutamide. Differences in results could be due to differences in dosages or formulations utilized.

Likelihood Unlikely Evidence B
Cytochrome P450 3A4 (Cyp3A4) Substrates

It is unclear if milk thistle inhibits CYP3A4; research is conflicting.
While laboratory research shows conflicting results, pharmacokinetic research shows that taking milk thistle extract 420-1350 mg daily does not significantly affect the metabolism of the CYP3A4 substrates irinotecan, midazolam, or indinavir. However, 8 case reports from the World Health Organization (WHO) adverse drug reaction database describe increased toxicity in patients taking milk thistle and cancer medications that are CYP3A4 substrates, including gefitinib, sorafenib, doxorubicin, and vincristine.

Likelihood Unlikely Evidence D
Estrogens

Theoretically, milk thistle might interfere with estrogen therapy through competition for estrogen receptors.
Animal research suggests that a milk thistle extract of silymarin binds to estrogen receptor beta.

Likelihood Possible Evidence D
Hmg-Coa Reductase Inhibitors ("Statins")

Theoretically, milk thistle might interfere with statin therapy by decreasing the activity of organic anion transporting polypeptide 1B1 (OATB1B1) and inhibiting breast cancer resistance protein (BCRP).
Preliminary evidence suggests that a milk thistle extract of silymarin can decrease the activity of the OATP1B1, which transports HMG-CoA reductase inhibitors into the liver to their site of action, and animal research shows this increases the maximum plasma concentration of pitavastatin and pravastatin. The silibinin component also inhibits BCRP, which transports statins from the liver into the bile for excretion. However, in a preliminary study in healthy males, silymarin 140 mg three times daily had no effect on the pharmacokinetics of a single 10 mg dose of rosuvastatin.

Likelihood Unlikely Evidence D
Indinavir (Crixivan)

Theoretically, milk thistle may induce cytochrome P450 3A4 (CYP3A4) enzymes and increase the metabolism of indinavir; however, results are conflicting.
One pharmacokinetic study shows that taking milk thistle (Standardized Milk Thistle, General Nutrition Corp.) 175 mg three times daily in combination with multiple doses of indinavir 800 mg every 8 hours decreases the mean trough levels of indinavir by 25%. However, results from the same pharmacokinetic study show that milk thistle does not affect the overall exposure to indinavir. Furthermore, two other pharmacokinetic studies show that taking specific milk thistle extract (Legalon, Rottapharm Madaus; Thisilyn, Nature's Way) 160-450 mg every 8 hours in combination with multiple doses of indinavir 800 mg every 8 hours does not reduce levels of indinavir.

Likelihood Unlikely Evidence B
Organic Anion-Transporting Polypeptide Substrates (Oatp)

Milk thistle may inhibit one form of OATP, OATP-B1, which could reduce the bioavailability and clinical effects of OATP-B1 substrates.
In vitro research shows that milk thistle inhibits OATP-B1. Two case reports from the World Health Organization (WHO) adverse drug reaction database describe increased toxicity in patients taking milk thistle and cancer medications that are OATP substrates, including sorafenib and methotrexate. OATPs are expressed in the small intestine and liver and are responsible for the uptake of drugs and other compounds into the body. Inhibition of OATP may reduce the bioavailability of oral drugs that are substrates of OATP.

Likelihood Possible Evidence D
P-Glycoprotein Substrates

Theoretically, milk thistle might increase the absorption of P-glycoprotein substrates. However, this effect does not seem to be clinically significant.
In vitro research shows that milk thistle can inhibit P-glycoprotein activity and 1 case report from the World Health Organization (WHO) adverse drug reaction database describes increased abdominal pain in a patient taking milk thistle and the cancer medication vincristine, a P-glycoprotein substrate, though this patient was also taking methotrexate. However, a small pharmacokinetic study in healthy volunteers shows that taking milk thistle (Enzymatic Therapy Inc.) 900 mg, standardized to 80% silymarin, in 3 divided doses daily for 14 days does not affect absorption of digoxin, a P-glycoprotein substrate.

Likelihood Unlikely Evidence B
Milk Thistle (Silybum marianum) seed std. extract full monograph & interactions

organic Dandelion7 drug types · 457 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, taking dandelion root along with anticoagulant or antiplatelet drugs might increase the risk of bruising and bleeding.
In vitro research suggests that dandelion root inhibits platelet aggregation.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, dandelion might increase the risk for hypoglycemia when used with antidiabetes drugs.
Laboratory research suggests that dandelion extract may have moderate alpha-glucosidase inhibitor activity and might also increase insulin secretion. Also, in a case report, a 58-year-old woman with type 2 diabetes who was being treated with insulin developed hypoglycemia 2 weeks after beginning to eat salads containing dandelion.

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

Theoretically, dandelion might increase levels of drugs metabolized by CYP1A2.
Laboratory research suggests that dandelion might inhibit CYP1A2. So far, this interaction has not been reported in humans. However, until more is known, watch for an increase in the levels of drugs metabolized by CYP1A2 in patients taking dandelion.

Likelihood Possible Evidence D
Glucuronidated Drugs

Theoretically, dandelion might increase the clearance of drugs that are UDP-glucuronosyltransferase substrates.
There is some preliminary evidence that dandelion might induce UDP-glucuronosyltransferase, a phase II enzyme.

Likelihood Possible Evidence D
Lithium

Theoretically, through diuretic effects, dandelion might reduce excretion and increase levels of lithium.
Animal research suggests that dandelion has diuretic properties. As diuretics can increase serum lithium levels, the dose of lithium might need to be decreased when taken with dandelion.

Likelihood Probable Evidence D
Potassium-Sparing Diuretics

Theoretically, dandelion might increase the risk of hyperkalemia when taken with potassium-sparing diuretics.
Dandelion contains significant amounts of potassium.

Likelihood Possible Evidence D
Quinolone Antibiotics

Theoretically, dandelion might lower fluoroquinolone levels.
Animal research shows that dandelion reduces absorption of ciprofloxacin and can lower levels by 73%. However, this effect has not been reported in humans.

Likelihood Possible Evidence D
organic Dandelion full monograph & interactions

Parsley8 drug types · 443 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, parsley might increase the risk of bleeding when taken with anticoagulant or antiplatelet drugs.
Animal research suggests that parsley has antiplatelet effects.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, parsley might increase the risk of hypoglycemia when taken with antidiabetes drugs.
Animal research suggests that parsley might decrease blood glucose. Monitor blood glucose levels closely. Dose adjustments might be necessary.

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

Theoretically, parsley might increase serum levels of CYP1A2 substrates.
Laboratory research suggests that parsley can inhibit CYP1A2.

Likelihood Possible Evidence D
Diuretic Drugs

Theoretically, parsley might enhance or interfere with the effects of diuretic drugs.
Animal research suggests that parsley seed extract increases urine elimination. Parsley leaf and root might also interfere with diuretic therapy due their purported aquaretic effects.

Likelihood Possible Evidence D
Pentobarbital (Nembutal)

Theoretically, parsley might increase the duration of pentobarbital effects.
Animal research suggests that parsley juice prolongs the action of pentobarbital, perhaps by decreasing cytochrome P450 levels. It is not known if this occurs in humans or if this applies to other barbiturates or sedatives.

Likelihood Possible Evidence D
Sirolimus (Rapamune)

Theoretically, large quantities of parsley might increase sirolimus levels.
In one case report, an adult female with a history of kidney transplant presented with elevated blood sirolimus levels, approximately 4-7 times greater than previous measures, after daily consumption of a juice containing approximately 30 grams of parsley for 7 days. Sirolimus levels returned to normal a week after the parsley juice was discontinued.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Theoretically, large amounts of parsley leaf and root might decrease the effects of warfarin.
Parlsey contains vitamin K.

Likelihood Possible Evidence D
Aspirin

Theoretically, aspirin might increase the severity of allergic reactions to parsley.
In one case, severe urticaria and swelling were reported after taking aspirin with parsley in an individual with a known mild parsley allergy.

Likelihood Unlikely Evidence D
Parsley full monograph & interactions

Organic Calendula1 drug type · 248 drugs

Cns Depressants

Theoretically, calendula might have additive effects when used with CNS depressants, although this appears to be unlikely.
Although some animal research has suggested that a saponoside constituent in calendula may have sedative effects, calendula has been used for over 30 years without reports of sedation in humans.

Likelihood Unlikely Evidence D
Organic Calendula full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Collinsonia Formula, from the product label.

Genestra Brands

Name
Seroyal USA
City
Pittsburgh
State
PA
ZipCode
15275
Phone Number
1-888-737-6925
Web Address
seroyal.com
Pharmacist Counseling Corner

Collinsonia Formula by Genestra Brands: Common Questions

Does Collinsonia Formula by Genestra Brands interact with any medications?
Yes. Based on its ingredients, Collinsonia Formula has a known interaction with 2,162 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Collinsonia Formula contains 7 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 this while I'm on warfarin?
No—parsley in this product contains vitamin K, which can reduce warfarin's effect, and milk thistle may increase warfarin levels. Both create unpredictable blood-thinning. Don't take this with warfarin without your doctor's approval.
Can this product help with varicose veins?
The evidence isn't established in the data we hold. Dandelion and witch hazel are traditionally used for vein support, but we don't have reliable evidence they work for varicose veins.
What are the most common side effects?
Dandelion, the most likely culprit, may cause diarrhea, heartburn, or stomach discomfort at higher doses. Milk thistle may cause mild bloating, gas, or nausea, though these don't typically occur more often than with placebo.
Is this safe during pregnancy?
No. Parsley should be avoided in medicinal amounts during pregnancy, and both calendula and milk thistle lack enough safety data—pregnancy ratings advise against them. Talk to your doctor or pharmacist before use if you're pregnant.
What's parsley doing in a circulation supplement?
Parsley has traditionally been used to support circulation and has diuretic properties. However, in supplement doses it carries interactions with blood thinners, diabetes drugs, and water pills, so it's not a passive ingredient.
Can I take this if I have diabetes?
Parsley, dandelion, and milk thistle can all lower blood sugar. If you take diabetes medications, this product may increase your risk of low blood sugar—don't take it without checking with your doctor first.

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.

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Go deeper

The Full Monographs Behind Collinsonia Formula’s Ingredients

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

Herb & supplement monograph

Marshmallow

Interacts with 2,040 drugs

Marshmallow root is a traditional herb rich in soothing, gel-like fibers called mucilage, which is why it has long been used for coughs, sore throats, and stomach irritation. Evidence for th...

Read the full Marshmallow monograph → Herb & supplement monograph

Parsley

Interacts with 443 drugs

Parsley is a popular culinary herb that is safe to eat in normal food amounts and is a good source of vitamins K and C. It is traditionally used as a diuretic and for digestion, but solid hu...

Read the full Parsley monograph → Herb & supplement monograph

Calendula

Interacts with 248 drugs

Calendula is a flowering plant whose petals are used mainly in skin creams, oils, and ointments to soothe minor irritation and support wound healing. Some early research is promising for ski...

Read the full Calendula monograph → Herb & supplement monograph

Dandelion

Interacts with 457 drugs

Dandelion is a common plant used in food and traditional medicine, often promoted as a natural 'water pill' and digestive aid. Human evidence for these uses is very limited, so its benefits...

Read the full Dandelion monograph → Herb & supplement monograph

Witch Hazel

Witch hazel is a plant-based astringent used mostly on the skin for minor irritation, hemorrhoids, and oily skin. It is generally well tolerated as a topical product for short-term use, but...

Read the full Witch Hazel monograph → Herb & supplement monograph

Milk Thistle

Interacts with 954 drugs

Milk thistle is a popular herbal supplement most often used for liver health, and its main active component is a group of compounds called silymarin. While it is generally well tolerated, th...

Read the full Milk Thistle monograph →
Sources

Sources & How We Checked

Collinsonia Formula'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 138 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.

Marshmallow 5 references
  1. Monographs on the medicinal uses of plant drugs. Exeter, UK: European Scientific Co-op Phytother, 1997.
  2. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
  3. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
  4. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  5. Hage-Sleiman R, Mroueh M, Daher CF. Pharmacological evaluation of aqueous extract of Althaea officinalis flower grown in Lebanon. Pharm Biol 2011;49(3):327-33.

See these in context on the Marshmallow monograph →

Parsley 21 references
  1. Newall CA, Anderson LA, Philpson JD. Herbal Medicine: A Guide for Healthcare Professionals. London, UK: The Pharmaceutical Press, 1996.
  2. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
  3. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
  4. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  5. Robbers JE, Tyler VE. Tyler's Herbs of Choice: The Therapeutic Use of Phytomedicinals. New York, NY: The Haworth Herbal Press, 1999.
  6. Foster S, Tyler VE. Tyler's Honest Herbal, 4th ed., Binghamton, NY: Haworth Herbal Press, 1999. DOI
  7. Eberhard P, Gall HM, Muller I, Moller R. Dramatic augmentation of a food allergy by acetylsalicylic acid. J Allergy Clin Immunol 2000;105:844 PubMed
  8. Tunali T, Yarat A, Yanardag R, et al. Effect of parsley (Petroselinum crispum) on the skin of STZ induced diabetic rats. Phytother Res 1999;13:138-41.. DOI
  9. 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
  10. Ciganda C, and Laborde A. Herbal infusions used for induced abortion. J Toxicol.Clin Toxicol. 2003;41:235-239. PubMed
  11. Jakovljevic, V., Raskovic, A., Popovic, M., and Sabo, J. The effect of celery and parsley juices on pharmacodynamic activity of drugs involving cytochrome P450 in their metabolism. Eur.J Drug Metab Pharmacokinet. 2002;27(3):153-156. PubMed
  12. Kreydiyyeh, S. I. and Usta, J. Diuretic effect and mechanism of action of parsley. J Ethnopharmacol 2002;79(3):353-357. PubMed
  13. Yanardag, R., Bolkent, S., Tabakoglu-Oguz, A., and Ozsoy-Sacan, O. Effects of Petroselinum crispum extract on pancreatic B cells and blood glucose of streptozotocin-induced diabetic rats. Biol Pharm Bull. 2003;26(8):1206-1210. PubMed
  14. Bolkent, S., Yanardag, R., Ozsoy-Sacan, O., and Karabulut-Bulan, O. Effects of parsley (Petroselinum crispum) on the liver of diabetic rats: a morphological and biochemical study. Phytother.Res 2004;18(12):996-999.
  15. Ozsoy-Sacan, O., Yanardag, R., Orak, H., Ozgey, Y., Yarat, A., and Tunali, T. Effects of parsley (Petroselinum crispum) extract versus glibornuride on the liver of streptozotocin-induced diabetic rats. J Ethnopharmacol 3-8-2006;104(1-2):175-181. PubMed
  16. Peterson, S., Lampe, J. W., Bammler, T. K., Gross-Steinmeyer, K., and Eaton, D. L. Apiaceous vegetable constituents inhibit human cytochrome P-450 1A2 (hCYP1A2) activity and hCYP1A2-mediated mutagenicity of aflatoxin B1. Food Chem.Toxicol. 2006;44(9):147 PubMed
  17. Gadi, D., Bnouham, M., Aziz, M., Ziyyat, A., Legssyer, A., Legrand, C., Lafeve, F. F., and Mekhfi, H. Parsley extract inhibits in vitro and ex vivo platelet aggregation and prolongs bleeding time in rats. J Ethnopharmacol 8-17-2009;125(1):170-174. PubMed
  18. Arslan S, Ucar R, Caliskaner AZ. A Cases of Near-fatal Anaphylaxis: Parsley "Over-use" as an Herbal Remedy. Med Arch. 2014;68(6):426-7.
  19. Foti C, Cassano N, Mistrello G, Amato S, Romita P, Vena GA. Contact urticaria to raw arugula and parsley. Ann Allergy Asthma Immunol. 2011 May;106(5):447-8. PubMed
  20. Farzaei MH, Abbasabadi Z, Ardekani MR, Rahimi R, Farzaei F. Parsley: a review of ethnopharmacology, phytochemistry and biological activities. J Tradit Chin Med. 2013;33(6):815-26. PubMed
  21. Kurtaran M, Koc NS, Aksun MS, Yildirim T, Yilmaz SR, Erdem Y. Petroselinum crispum, a commonly consumed food, affects sirolimus level in a renal transplant recipient: a case report. Ther Adv Drug Saf 2021;12:20420986211009358.

See these in context on the Parsley monograph →

Calendula 9 references
  1. Newall CA, Anderson LA, Philpson JD. Herbal Medicine: A Guide for Healthcare Professionals. London, UK: The Pharmaceutical Press, 1996.
  2. Reider N, Komericki P, Hausen BM, et al. The seamy side of natural medicines: contact sensitization to arnica (Arnica montana L.) and marigold (Calendula officinalis L.). Contact Dermatitis 2001;45:269-72..
  3. Gol'dman II. [Anaphylactic shock after gargling with an infusion of Calendula]. Klin Med (Mosk) 1974;52:142-3.
  4. Paulsen E. Contact sensitization from Compositae-containing herbal remedies and cosmetics. Contact Dermatitis 2002;47:189-98. PubMed
  5. Bojadjiev C. On the sedative and hypotensive effect of preparations from the plant Calendula officinalis. Nauch Trud Visshi Med Inst Sof 1964;43:15-20.
  6. Samochowiec L. Pharmacological study of saponosides from Aralia mandshurica Rupr. et Maxim and Calendula officinalis L. Herba Pol. 1983;29:151-155.
  7. Madisetti M, Kelechi TJ, Mueller M, Amella EJ, Prentice MA. Feasibility, acceptability, and tolerability of RGN107 in the palliative wound care management of chronic wound symptoms. J Wound Care. 2017;26(Sup1):S25-S34. PubMed
  8. Final Assessment report on Calendula officinalis L., flos. European Medicines Agency: Committee on Herbal Medicinal Products (HMPC). 2018. EMA/HMPC/603409/2017. Available at: https://www.ema.europa.eu/en/documents/herbal-report/final-assessment-report-cal
  9. Puaratanaarunkon T, Washrawirul C, Chuenboonngarm N, Noppakun N, Asawanonda P, Kumtornrut C. Efficacy and safety of a facial serum containing snail secretion filtrate, Calendula officinalis, and Glycyrrhiza glaba root extract in the treatment of maskne: A

See these in context on the Calendula monograph →

Dandelion 27 references
  1. Maliakal PP, Wanwimolruk S. Effect of herbal teas on hepatic drug metabolizing enzymes in rats. J Pharm Pharmacol 2001;53:1323-9. PubMed
  2. Williams CA, Goldstone F, Greenham J. Flavonoids, cinnamic acids and coumarins from the different tissues and medicinal preparations of Taraxacum officinale. Phytochemistry 1996;42:121-7. PubMed
  3. Hussain Z, Waheed A, Qureshi RA, et al. The effect of medicinal plants of Islamabad and Murree region of Pakistan on insulin secretion from INS-1 cells. Phytother Res 2004;18:73-7. PubMed
  4. Racz-Kotilla E, Racz G, Solomon A. The action of Taraxacum officinale extracts on the body weight and diuresis of laboratory animals. Planta Med 1974;26:212-7. PubMed
  5. Zhu M, Wong PY, Li RC. Effects of taraxacum mongolicum on the bioavailability and disposition of ciprofloxacin in rats. J Pharm Sci 1999;88:632-4. PubMed
  6. Jovanovic M, Mimica-Dukic N, Poljacki M, Boza P. Erythema multiforme due to contact with weeds: a recurrence after patch testing. Contact Dermatitis 2003;48:17-25. PubMed
  7. Chivato T, Juan F, Montoro A, Laguna R. Anaphylaxis induced by ingestion of a pollen compound. J Investig Allergol Clin Immunol 1996;6:208-9.
  8. Cohen SH, Yunginger JW, Rosenberg N, Fink JN. Acute allergic reaction after composite pollen ingestion. J Allergy Clin Immunol 1979;64:270-4. PubMed
  9. Lovell CR, Rowan M. Dandelion dermatitis. Contact Dermatitis 1991;25:185-8. PubMed
  10. Agarwal SC, Crook JR, Pepper CB. Herbal remedies -- how safe are they? A case report of polymorphic ventricular tachycardia/ventricular fibrillation induced by herbal medication used for obesity. Int J Cardiol 2006;106:260-1. PubMed
  11. Martín-Muñoz MF, Bartolome B, Caminoa M, et al. Bee pollen: a dangerous food for allergic children. Identification of responsible allergens. Allergol Immunopathol (Madr) 2010;38:263-5. PubMed
  12. Neef H, Cilli F, Declerck PJ, et al. Platelet anti-aggregating activity of Taraxacum officinale Weber. Phytotherapy Research 1996;10:s138-s140.
  13. Cuzzolin L, Zaffani S, and Benoni G. Safety implications regarding use of phytomedicines. Eur.J Clin Pharmacol. 2006;62:37-42. PubMed
  14. Posadzki, P., Watson, L. K., and Ernst, E. Adverse effects of herbal medicines: an overview of systematic reviews. Clin Med 2013;13(1):7-12. PubMed
  15. Wakelin, S. H., Marren, P., Young, E., and Shaw, S. Compositae sensitivity and chronic hand dermatitis in a seven-year-old boy. Br J Dermatol 1997;137(2):289-291. PubMed
  16. Ingber, A. Seasonal allergic contact dermatitis from Taraxacum officinale (dandelion) in an Israeli florist. Contact Dermatitis 2000;43(1):49.
  17. Rodriguez, B., Rodriguez, A., de Barrio, M., Tornero, P., and Baeza, M. L. Asthma induced by canary food mix. Allergy Asthma Proc. 2003;24(4):265-268.
  18. Syhaieva, I. A. [Efficiency of specific immunotherapy in treatment of patients with seasonal allergic rhinitis]. Lik.Sprava. 2006;(1-2):51-53.
  19. Catania, M. A., Oteri, A., Caiello, P., Russo, A., Salvo, F., Giustini, E. S., Caputi, A. P., and Polimeni, G. Hemorrhagic cystitis induced by an herbal mixture. South.Med.J. 2010;103(1):90-92. PubMed
  20. Goksu, E., Eken, C., Karadeniz, O., and Kucukyilmaz, O. First report of hypoglycemia secondary to dandelion (Taraxacum officinale) ingestion. Am J Emerg.Med 2010;28(1):111-112. PubMed
  21. Fernandez-Gonzalez, D., Gonzalez-Parrado, Z., Vega-Maray, A. M., Valencia-Barrera, R. M., Camazon-Izquierdo, B., De, Nuntiis P., and Mandrioli, P. Platanus pollen allergen, Pla a 1: quantification in the atmosphere and influence on a sensitizing populati
  22. Liang, K. L., Su, M. C., Shiao, J. Y., Wu, S. H., Li, Y. H., and Jiang, R. S. Role of pollen allergy in Taiwanese patients with allergic rhinitis. J Formos.Med Assoc. 2010;109(12):879-885. PubMed
  23. Yang, Y., Zhao, Y., Wang, C. S., Wang, X. D., and Zhang, L. [Prevalence of sensitization to aeroallergens in 10 030 patients with allergic rhinitis]. Zhonghua Er.Bi Yan.Hou Tou.Jing.Wai Ke Za Zhi 2011;46(11):914-920.
  24. Davies, M. G. and Kersey, P. J. Contact allergy to yarrow and dandelion. Contact Dermatitis 1986;14(4):256-257. PubMed
  25. Collins JM and Miller DR. Dandelion green bezoar following antrectomy and vagotomy - case report. J Kansas Med Soc 1966;67(6):303-304.
  26. Moriarty B, Pinney JH, Owen-Casey MP, Rustin MH, Deroide F, Laing C, Davenport A. Digital necrosis from dandelion tea. Br J Dermatol. 2013 Jul;169(1):227-30. PubMed
  27. Onal S, Timur S, Okutucu B, Zihnioglu F. Inhibition of alphaglucosidase by aqueous extracts of some potent antidiabetic medicinal herbs. Prep Biochem Biotechnol 2005;35:29-36.

See these in context on the Dandelion monograph →

Witch Hazel 7 references
  1. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
  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. Robbers JE, Tyler VE. Tyler's Herbs of Choice: The Therapeutic Use of Phytomedicinals. New York, NY: The Haworth Herbal Press, 1999.
  4. Hormann HP, Korting HC. Evidence for the efficacy and safety of topical herbal drugs in dermatology: part I: anti-inflammatory agents. Phytomedicine 1994;1:161-71. PubMed
  5. Wolff, H. H. and Kieser, M. Hamamelis in children with skin disorders and skin injuries: results of an observational study. Eur.J.Pediatr. 2007;166(9):943-948. PubMed
  6. Khanna, N. and Datta, Gupta S. Rejuvenating facial massage--a bane or boon? Int J Dermatol. 2002;41(7):407-410. PubMed
  7. Theisen LL, Erdelmeier CA, Spoden GA, Boukhallouk F, Sausy A, Florin L, Muller CP. Tannins from Hamamelis virginiana bark extract: characterization and improvement of the antiviral efficacy against influenza A virus and human papillomavirus. PLoS One. 201 PubMed

See these in context on the Witch Hazel monograph →

Milk Thistle 69 references
  1. Ferenci P, Dragosics B, Dittrich H, et al. Randomized controlled trial of silymarin treatment in patients with cirrhosis of the liver. J Hepatol 1989;9:105-13. PubMed
  2. Anon. Milk thistle: Effects on liver disease and cirrhosis and clinical adverse effects. Summary, Evidence Report/Technology Assessment: Number 21, September 2000. Agency for Healthcare Research and Quality, Rockville, MD. Available at: http://www.ahrq.g
  3. Beckmann-Knopp S, Rietbrock S, Weyhenmeyer R, et al. Inhibitory effects of silibinin on cytochrome P-450 enzymes in human liver microsomes. Pharmacol Toxicol 2000;86:250-6. PubMed
  4. Venkataramanan R, Ramachandran V, Komoroski BJ, et al. Milk thistle, a herbal supplement, decreases the activity of CYP3A4 and uridine diphosphoglucuronosyl transferase in human hepatocyte cultures. Drug Metab Dispos 2000;28:1270-3. DOI
  5. Kim DH, Jin YH, Park JB, Kobashi K. Silymarin and its components are inhibitors of beta-glucuronidase. Biol Pharm Bull 1994;17:443-5. PubMed
  6. Pares A, Planas R, Torres M, et al. Effects of silymarin in alcoholic patients with cirrhosis of the liver: results of a controlled, double-blind, randomized and multicenter trial. J Hepatol 1998;28:615-21. PubMed
  7. Piscitelli SC, Formentini E, Burstein AH, et al. Effect of milk thistle on the pharmacokinetics of indinavir in healthy volunteers. Pharmacotherapy 2002;22:551-6. PubMed
  8. Boerth J, Strong KM. The clinical utility of milk thistle (Silybum marianum) in cirrhosis of the liver. J Herb Pharmacother 2002;2:11-7.
  9. Tanamly MD, Tadros F, Labeeb S, et al. Randomised double-blinded trial evaluating silymarin for chronic hepatitis C in an Egyptian village: study description and 12-month results. Dig Liver Dis 2004;36:752-9. PubMed
  10. Gurley BJ, Gardner SF, Hubbard MA, et al. In vivo assessment of botanical supplementation on human cytochrome P450 phenotypes: Citrus aurantium, Echinacea purpurea, milk thistle, and saw palmetto. Clin Pharmacol Ther 2004;76:428-40. .
  11. Huseini HF, Larijani B, Heshmat R, et al. The efficacy of Silybum marianum (L.) Gaertn. (silymarin) in the treatment of type II diabetes: a randomized, double-blind, placebo-controlled, clinical trial. Phytother Res 2006;20;1036-9.
  12. Deng JW, Shon JH, Shin HJ, et al. Effect of silymarin supplement on the pharmacokinetics of rosuvastatin. Pharm Res 2008;25:1807-14. PubMed
  13. Kim CS, Choi SJ, Park CY, et al. Effects of silybinin on the pharmacokinetics of tamoxifen and its active metabolite, 4-hydroxytamoxifen in rats. Anticancer Res 2010;30:79-85.
  14. Sridar C, Goosen TC, Kent UM, et al. Silybin inactivates cytochromes P450 3A4 and 2C9 and inhibits major hepatic glucuronosyltransferases. Drug Metab Dispos 2004;32:587-94. PubMed
  15. van Erp NP, Baker SD, Zhao M, et al. Effect of milk thistle (Silybum marianum) on the pharmacokinetics of irinotecan. Clin Cancer Res 2005;11:7800-6.
  16. Budzinski JW, Trudeau VL, Drouin CE, et al. Modulation of human cytochrome P450 3A4 (CYP3A4) and P-glycoprotein (P-gp) in Caco-2 cell monolayers by selected commercial-source milk thistle and goldenseal products. Can J Physiol Pharmacol 2007;85:966-78.
  17. Doehmer J, Weiss G, McGregor GP, Appel K. Assessment of a dry extract from milk thistle (Silybum marianum) for interference with human liver cytochrome-P450 activities. Toxicol In Vitro 2011;25:21-7. PubMed
  18. Jiao Z, Shi XJ, Li ZD, et al. Population pharmacokinetics of sirolimus in de novo Chinese adult renal transplant patients. Br.J.Clin.Pharmacol. 2009;68(1):47-60.
  19. Gurley, B. J., Barone, G. W., Williams, D. K., Carrier, J., Breen, P., Yates, C. R., Song, P. F., Hubbard, M. A., Tong, Y., and Cheboyina, S. Effect of milk thistle (Silybum marianum) and black cohosh (Cimicifuga racemosa) supplementation on digoxin phar
  20. Allain, H., Schuck, S., Lebreton, S., Strenge-Hesse, A., Braun, W., Gandon, J. M., and Brissot, P. Aminotransferase levels and silymarin in de novo tacrine-treated patients with Alzheimer's disease. Dement.Geriatr.Cogn Disord. 1999;10(3):181-185. PubMed
  21. Angulo, P., Patel, T., Jorgensen, R. A., Therneau, T. M., and Lindor, K. D. Silymarin in the treatment of patients with primary biliary cirrhosis with a suboptimal response to ursodeoxycholic acid. Hepatology 2000;32(5):897-900. PubMed
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  25. Gharagozloo, M., Moayedi, B., Zakerinia, M., Hamidi, M., Karimi, M., Maracy, M., and Amirghofran, Z. Combined therapy of silymarin and desferrioxamine in patients with beta-thalassemia major: a randomized double-blind clinical trial. Fundam.Clin.Pharmaco
  26. Ladas, E. J., Kroll, D. J., Oberlies, N. H., Cheng, B., Ndao, D. H., Rheingold, S. R., and Kelly, K. M. A randomized, controlled, double-blind, pilot study of milk thistle for the treatment of hepatotoxicity in childhood acute lymphoblastic leukemia (ALL PubMed
  27. Sayyah, M., Boostani, H., Pakseresht, S., and Malayeri, A. Comparison of Silybum marianum (L.) Gaertn. with fluoxetine in the treatment of Obsessive-Compulsive Disorder. Prog.Neuropsychopharmacol.Biol.Psychiatry 3-17-2010;34(2):362-365. PubMed
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  29. Ramirez-Santos, A., Perez-Bustillo, A., Gonzalez-Sixto, B., Suarez-Amor, O., and Rodriguez-Prieto, M. A. [Acute generalized exanthematous pustulosis due to milk thistle (Silybum marianum) tea]. Actas Dermosifiliogr. 2011;102(9):744-745. DOI
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  42. Schuppan D, Strosser W, Burkard G, and et al. Influence of Legalon(TM) 140 on the metabolism of collagen in patients with chronic liver disease--Review by measurement of PIIINP-values. Zeitschrift fur Allgemeinmedizin 1998;74:577-584.
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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

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