Interactions on record — worth a quick check against your medications. Based on 7 of 9 ingredients. Check your meds →
Dietary supplement

Lappa Ingredients & Drug Interactions

by Nestmann

Lappa label
See full label image
Liquid Category: Botanical
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 23, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Lappa 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

Lappa is a dietary supplement by Nestmann with 9 active ingredients. Its ingredients are commonly taken for sore throat and cough, heartburn and stomach upset, mouth ulcers and digestive complaints.Based on those ingredients, 2,139 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Acacia, Licorice, Fennel. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Lappa by Nestmann

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

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HelloPharmacist Scorecard of Lappa by Nestmann

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 Aug 13, 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 9 of its 9 active ingredients.
  • “Liquid Extract from” is listed as a grouped ingredient — the label doesn't break down how much of each component you get.

Lappa contains 9 ingredients total, 7 of which we can identify. The active components include licorice root, heartsease, butternut (also called black walnut), fennel seed, burdock root, Mexican sarsaparilla, European white birch, thyme, and acacia (gum arabic).

These are delivered in a liquid extract form. The product also contains ethyl alcohol and water as inactive ingredients.

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: Dysmenorrhea — rated "Possibly Effective" (Fennel) (Natural Medicines).
  • On file: Atopic dermatitis (eczema) — rated "Possibly Effective" (Licorice) (Natural Medicines).
  • On file: Canker sores — rated "Possibly Effective" (Licorice) (Natural Medicines).

The evidence for what this product actually does is limited. Licorice is rated possibly effective for canker sores and atopic dermatitis (eczema), but the other ingredients either have insufficient evidence in our data or no effectiveness ratings at all.

Fennel is possibly effective for dysmenorrhea (menstrual cramps), but burdock, thyme, sarsaparilla, acacia, butternut, and the two ingredients we couldn't check show insufficient evidence to rate their effectiveness for any condition.

The evidence, ingredient by ingredient Licorice Butternut Fennel Burdock Sarsaparilla Thyme Gum Arabic

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 7 of the 7 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 7 of 7.
  • General safety write-ups exist for 7 of 7.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Licorice is generally well tolerated in small amounts but can cause serious problems at high doses or with long-term use—the most common side effects are headache, nausea, and vomiting. It should be avoided in pregnancy (the safety data advise against it) and while breastfeeding due to insufficient information.

Butternut acts as a laxative and can cause diarrhea and digestive upset; it's rated likely unsafe in pregnancy and lactation. Fennel is rated possibly unsafe in pregnancy and lactation due to limited safety data and hormone-like effects.

Thyme is rated likely safe in pregnancy and lactation at food amounts, but medicinal doses aren't well studied. Burdock, sarsaparilla, and acacia have insufficient safety information for pregnancy and breastfeeding.

Contact allergies and skin reactions have been reported with burdock, fennel, and thyme topical use.

Side effects, ingredient by ingredient Licorice Butternut Fennel Burdock Sarsaparilla Thyme Gum Arabic

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?
  • 7 of the 7 matched ingredients can interact with medications — Burdock, Gum Arabic, Fennel, Sarsaparilla, Butternut, among others.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; heart-rhythm medications; lithium.
  • For scale: 2,140 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 Lappa, double-check your medications against these drug types: heart medications like digoxin and blood thinners like warfarin (Moderate severity with licorice and butternut, and with fennel and thyme for warfarin); loop diuretics and other potassium-depleting drugs (Moderate with licorice and butternut); birth control pills and hormone replacement therapy (Moderate with fennel); lithium (Moderate with sarsaparilla); liver-metabolized drugs processed by CYP2B6, CYP2C19, and CYP3A4 pathways (Moderate with licorice and fennel); sedatives like midazolam (Moderate with licorice); and antibiotics like amoxicillin and ciprofloxacin (Moderate with acacia and fennel respectively). If you take any of these, check with your own pharmacist or doctor before starting.

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.

Lappa is a multi-ingredient herbal liquid that may help with certain skin conditions or digestive issues, but the evidence for most ingredients is thin. Because it contains licorice and other herbs with multiple drug interactions—affecting over 2,000 medications across all ingredients—this is not a product to start without checking it against your specific prescriptions first.

Talk with your pharmacist or doctor before taking it, especially if you take heart medications, blood thinners, birth control, or any regular prescriptions.

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

Assessment coverage: 7 of 9 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Sep 25, 2013.

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 Lappa, straight from the product label.

Brand Nestmann
Net contents 3.38 fl. Oz.; 100 mL
Market status On market
Date entered into DSLD Sep 25, 2013
DSLD ID 25300
Product type Botanical
Supplement form Liquid
Dietary claims / uses All Other
Intended target group(s) Adult (18 - 50 Years), Children (All)
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 Lappa by Nestmann, 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:
0.33 mL
Maximum serving Sizes:
1 mL
Servings per container
100
IngredientAmount% DV
Licorice8 mg--
Liquid Extract from0 NP--
Heartsease16 mg--
Butternut16 mg--
Fennel6 mg--
Burdock20 mg--
Mexican Sarsaparilla20 mg--
European White Birch16 mg--
Thyme16 mg--
Acacia12 mg--

Other ingredients: Ethyl Alcohol, Water

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

Suggested Use: 20-30 drops in 1 cup pure water 3 times daily. Children receive 1/2 or less of the above described dosage.

Precautions

Warning: If you are pregnant or breastfeeding, ask a health professional before use.

Keep out of reach of children.

Tamper Evident: Use this product only if tamper evident ring has not been broken away from base of cap.

General Statements

Lot No: 0790 Exp: 10/15

30

>>NESTMANN<<

Made in Germany Nestmann + Co Zapfendorf/Barnberg

FDA Statement of Identity

Herbal Liquid Extract Supplement

Seals/Symbols

MPI

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

See for yourself

Lappa by Nestmann label

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

Lappa 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 Lappa by Nestmann

These are the 9 active ingredients this product is made of. Select any to open its full monograph.

Serving size0.33 mL Dosage formLiquid Servings per container100 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.

Liquid Extract from

0 NP per serving

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

Interaction report

Lappa by Nestmann Drug Interactions

Want to check YOUR meds against Lappa?

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
2,139Drugs
2,136 Moderate 3 Minor

Ingredients driving the most interactions

Acacia 2,022
Licorice 1,040
Fennel 740
Thyme 379
Butternut 122

Individual Drug Interactions

The ingredients in Lappa interact with 2,139 drugs. Click any drug to see the details.

7 of the 9 ingredients in Lappa interact with drugs. Each result below shows which ingredient is responsible. Acacia Licorice Fennel Thyme Butternut Burdock Mexican Sarsaparilla

Each ingredient & the kinds of drugs it affects

For each ingredient in Lappa 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.

Acacia2 drug types · 2,022 drugs

Amoxicillin (Amoxil, Trimox)

Gum arabic can reduce the absorption of amoxicillin.
A small study in healthy volunteers shows that taking amoxicillin and gum arabic concurrently significantly reduces the absorption of amoxicillin. Separate doses of amoxicillin from gum arabic by at least 2 hours.

Likelihood Probable Evidence B
Oral Drugs

Theoretically, gum arabic can alter the absorption of oral drugs due to its fiber content.
Gum arabic has been used as a suspending osmotic agent in drug formulations. It might improve bioavailability of water-insoluble drugs like naproxen, but reduce absorption of polar drugs like amoxicillin. To avoid changes in absorption, take gum arabic 30-60 minutes after oral medications.

Likelihood Possible Evidence B
Acacia full monograph & interactions

Licorice18 drug types · 1,040 drugs

Antihypertensive Drugs

Theoretically, licorice might reduce the effects of antihypertensive drugs.
In human research, licorice increases blood pressure in a dose-dependent manner.

Likelihood Possible Evidence B
Cisplatin (Platinol-Aq)

Theoretically, licorice might reduce the effects of cisplatin.
In animal research, licorice diminished the therapeutic efficacy of cisplatin.

Likelihood Possible Evidence D
Corticosteroids

Theoretically, concomitant use of licorice and corticosteroids might increase the side effects of corticosteroids.
Case reports suggest that concomitant use of licorice and oral corticosteroids, such as hydrocortisone, can potentiate the duration of activity and increase blood levels of corticosteroids. Additionally, in one case report, a patient with neurogenic orthostatic hypertension stabilized on fludrocortisone 0.1 mg twice daily developed pseudohyperaldosteronism after recent consumption of large amounts of black licorice.

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

Theoretically, licorice might increase levels of drugs metabolized by CYP2B6.
In vitro research shows that licorice extract and glabridin, a licorice constituent, inhibit CYP2B6 isoenzymes. Licorice extract from the species G. uralensis seems to inhibit CYP2B6 isoenzymes to a greater degree than G. glabra extract in vitro. Theoretically, these species of licorice might increase levels of drugs metabolized by CYP2B6; however, these interactions have not yet been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2C19 (Cyp2C19) Substrates

Theoretically, licorice might increase levels of drugs metabolized by CYP2C19.
In vitro, licorice extracts from the species G. glabra and G. uralensis inhibit CYP2C19 isoenzymes in vitro. Theoretically, these species of licorice might increase levels of drugs metabolized by CYP2C19; however, this interaction has not yet been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2C8 (Cyp2C8) Substrates

Theoretically, licorice might increase levels of drugs metabolized by CYP2C8.
In vitro, licorice extract from the species G. glabra and G. uralensis inhibits CYP2C8 isoenzymes. Theoretically, these species of licorice might increase levels of drugs metabolized by CYP2C8; however, this interaction has not yet been reported in humans.

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

Theoretically, licorice might increase or decrease levels of drugs metabolized by CYP2C9.
There is conflicting evidence about the effect of licorice on CYP2C9 enzyme activity. In vitro research shows that extracts from the licorice species G. glabra and G. uralensis moderately inhibit CYP2C9 isoenzymes. However, evidence from an animal model shows that licorice extract from the species G. uralensis can induce hepatic CYP2C9 activity. Until more is known, licorice should be used cautiously in people taking CYP2C9 substrates.

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

Theoretically, licorice might increase or decrease levels of drugs metabolized by CYP3A4.
Pharmacokinetic research shows that the licorice constituent glycyrrhizin, taken in a dosage of 150 mg orally twice daily for 14 days, modestly decreases the area under the concentration-time curve of midazolam by about 20%. Midazolam is a substrate of CYP3A4, suggesting that glycyrrhizin modestly induces CYP3A4 activity. Animal research also shows that licorice extract from the species G. uralensis induces CYP3A4 activity. However, licorice extract from G. glabra species appear to inhibit CYP3A4-induced metabolism of testosterone in vitro. It is thought that the G. glabra inhibits CYP3A4 due to its constituent glabridin, which is a moderate CYP3A4 inhibitor in vitro and not present in other licorice species. Until more is known, licorice should be used cautiously in people taking CYP3A4 substrates.

Likelihood Possible Evidence B
Digoxin (Lanoxin)

Theoretically, concomitant use of licorice with digoxin might increase the risk of cardiac toxicity.
Overuse or misuse of licorice with cardiac glycoside therapy might increase the risk of cardiac toxicity due to potassium loss.

Likelihood Possible Evidence D
Diuretic Drugs

Theoretically, concomitant use of licorice with diuretic drugs might increase the risk of hypokalemia.
Overuse of licorice might compound diuretic-induced potassium loss. In one case report, a 72-year-old male with a past medical history of hypertension, type 2 diabetes, hyperlipidemia, arrhythmia, stroke, and hepatic dysfunction was hospitalized with severe hypokalemia and uncontrolled hypertension due to pseudohyperaldosteronism. This was thought to be provoked by concomitant daily consumption of a product containing 225 mg of glycyrrhizin, a constituent of licorice, and hydrochlorothiazide 12.5 mg for 1 month.

Likelihood Possible Evidence D
Estrogens

Theoretically, licorice might increase or decrease the effects of estrogen therapy.
Theoretically, licorice might interfere with estrogen therapy due to estrogenic and anti-estrogenic effects.

Likelihood Possible Evidence D
Loop Diuretics

Theoretically, loop diuretics might increase the mineralocorticoid effects of licorice.
Theoretically, loop diuretics might enhance the mineralocorticoid effects of licorice by inhibiting the enzyme that converts cortisol to cortisone; however, bumetanide (Bumex) does not appear to have this effect.

Likelihood Possible Evidence D
Midazolam (Versed)

Theoretically, licorice might decrease levels of midazolam.
In humans, the licorice constituent glycyrrhizin appears to moderately induce the metabolism of midazolam. This is likely due to induction of cytochrome P450 3A4 by licorice. Until more is known, licorice should be used cautiously in people taking midazolam.

Likelihood Possible Evidence B
P-Glycoprotein Substrates

Theoretically, licorice might decrease the absorption of P-glycoprotein substrates.
In vitro research shows that licorice can increase P-glycoprotein activity.

Likelihood Possible Evidence D
Paclitaxel (Abraxane, Onxol)

Theoretically, licorice might decrease plasma levels and clinical effects of paclitaxel.
Multiple doses of licorice taken concomitantly with paclitaxel might reduce the effectiveness of paclitaxel. Animal research shows that licorice 3 grams/kg given orally for 14 days before intravenous administration of paclitaxel decreases the exposure to paclitaxel and increases its clearance. Theoretically, this occurs because licorice induces cytochrome P450 3A4 enzymes, which metabolize paclitaxel. Notably, a single dose of licorice did not affect exposure or clearance of paclitaxel.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Theoretically, licorice might decrease plasma levels and clinical effects of warfarin.
Licorice seems to increase metabolism and decrease levels of warfarin in animal models. This is likely due to induction of cytochrome P450 2C9 (CYP2C9) metabolism by licorice. Advise patients taking warfarin to avoid taking licorice.

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

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

Likelihood Possible Evidence D
Methotrexate (Trexall, Others)

Theoretically, licorice might increase levels of methotrexate.
Animal research suggests that intravenous administration of glycyrrhizin, a licorice constituent, and high-dose methotrexate may delay methotrexate excretion and increase systemic exposure, leading to transient elevations in liver enzymes and total bilirubin. This interaction has not yet been reported in humans.

Likelihood Unlikely Evidence D
Licorice full monograph & interactions

Fennel6 drug types · 740 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, fennel might increase the risk of bleeding when used with antiplatelet or anticoagulant drugs.

Animal research suggests that fennel oil has antithrombotic and antiplatelet effects.

Likelihood Possible Evidence D
Ciprofloxacin (Cipro)

Theoretically, fennel might decrease the levels and clinical effects of ciprofloxacin.

Animal research shows that fennel reduces ciprofloxacin bioavailability by nearly 50%, possibly due to the metal cations such as calcium, iron, and magnesium contained in fennel. This study also found that fennel increased tissue distribution and slowed elimination of ciprofloxacin.

Likelihood Probable Evidence D
Contraceptive Drugs

Theoretically, taking large amounts of fennel might decrease the effects of contraceptive drugs due to competition for estrogen receptors.

Some constituents of fennel have estrogenic activity.

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

Theoretically, fennel might increase levels of drugs metabolized by CYP3A4.

In vitro research suggests that fennel inhibits CYP3A4 enzyme activity. This effect has not been reported in humans.

Likelihood Possible Evidence D
Estrogens

Theoretically, taking large amounts of fennel might interfere with hormone replacement therapy due to competition for estrogen receptors.

Some constituents of fennel have estrogenic activity.

Likelihood Possible Evidence D
Tamoxifen (Nolvadex)

Theoretically, taking large amounts of fennel might decrease the antiestrogenic effect of tamoxifen.

Some constituents of fennel have estrogenic activity, which may interfere with the antiestrogenic activity of tamoxifen.

Likelihood Possible Evidence D
Fennel full monograph & interactions

Thyme4 drug types · 379 drugs

Anticholinergic Drugs

Theoretically, concurrent use of anticholinergic drugs and thyme essential oil might reduce the effects of anticholinergic drugs.
In vitro evidence suggests that thyme essential oil and specific essential oil constituents like thymohydroquinone and carvacrol can inhibit acetylcholinesterase (AChE). However, this effect has not been observed in humans.

Likelihood Possible Evidence D
Anticoagulant/Antiplatelet Drugs

Theoretically, thyme leaf extract might have additive effects with anticoagulant or antiplatelet drugs.
In vitro and animal research suggests that thyme leaf extract has antiplatelet effects. However, this effect has not been observed in humans.

Likelihood Possible Evidence D
Cholinergic Drugs

Theoretically, concurrent use of cholinergic drugs and thyme essential oil might cause additive cholinergic effects.
In vitro evidence suggests that thyme essential oil and specific essential oil constituents like thymohydroquinone and carvacrol can inhibit acetylcholinesterase (AChE). However, this effect has not been observed in humans.

Likelihood Possible Evidence D
Estrogens

Theoretically, thyme might competitively inhibit the effects of estrogen replacement therapy.
In vitro research shows that thyme has estrogen receptor-binding activity and phytoestrogen content. However, this effect has not been observed in humans.

Likelihood Possible Evidence D
Thyme full monograph & interactions

Butternut5 drug types · 122 drugs

Corticosteroids

Butternut has stimulant laxative effects. Theoretically, concomitant use of corticosteroids with butternut can increase the risk of potassium depletion.

Likelihood Possible Evidence D
Digoxin (Lanoxin)

Butternut has stimulant laxative effects. Theoretically, potassium depletion associated with butternut might increase the risk of digoxin toxicity.

Likelihood Possible Evidence D
Diuretic Drugs

Butternut has stimulant laxative effects. Theoretically, overuse of butternut might compound diuretic-induced potassium loss. There is some concern that people receiving butternut along with potassium-depleting diuretics might be at an increased risk for hypokalemia.
Some diuretics that can deplete potassium include chlorothiazide (Diuril), chlorthalidone (Thalitone), furosemide (Lasix), hydrochlorothiazide (HCTZ, Hydrodiuril, Microzide), and others.

Likelihood Possible Evidence D
Stimulant Laxatives

Butternut has stimulant laxative effects. Concomitant use with stimulant laxative medications might compound fluid and electrolyte loss.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Butternut has stimulant laxative effects. In some people butternut 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 butternut.

Likelihood Possible Evidence D
Butternut full monograph & interactions

Burdock1 drug type · 122 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, taking burdock with anticoagulant or antiplatelet drugs might increase the risk of bleeding.

In vitro research shows that lignans from burdock reduce rabbit platelet aggregation by inhibiting platelet activating factor. This interaction has not been reported in humans.

Likelihood Possible Evidence D
Burdock full monograph & interactions

Mexican Sarsaparilla2 drug types · 2 drugs

Digoxin (Lanoxin)

Theoretically, concomitant use of sarsaparilla with digoxin might increase the risk of cardiac toxicity.
Sarsaparilla is thought to have diuretic properties, which could potentially cause potassium loss. Overuse or misuse of sarsaparilla with cardiac glycoside therapy might increase the risk of cardiac toxicity due to potassium loss.

Likelihood Possible Evidence D
Lithium

Theoretically, sarsaparilla might increase the effects and adverse effects of lithium.
Sarsaparilla is thought to have diuretic properties. Due to these effects, sarsaparilla might reduce excretion and increase levels of lithium. The dose of lithium might need to be decreased.

Likelihood Probable Evidence D
Mexican Sarsaparilla full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Lappa, from the product label.

Nestmann

See all Nestmann products
Name
Marco Pharma Int'l
City
Roseburg
State
OR
ZipCode
97470
Pharmacist Counseling Corner

Lappa by Nestmann: Common Questions

Does Lappa by Nestmann interact with any medications?
Yes. Based on its ingredients, Lappa has a known interaction with 2,139 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Lappa contains 9 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 Lappa safe to take during pregnancy?
No. Licorice and butternut are rated unsafe in pregnancy, fennel is rated possibly unsafe, and burdock and sarsaparilla have insufficient data—we advise against use. Talk with your doctor before taking any herbal supplement while pregnant.
Can I take Lappa while breastfeeding?
It's not recommended. Licorice, butternut, burdock, and sarsaparilla all lack enough safety information for breastfeeding, and fennel is rated possibly unsafe. Check with your doctor or pharmacist for personalized advice.
What is licorice in this product used for?
Licorice is included for its possible effectiveness in treating canker sores and atopic dermatitis (eczema). However, it carries the most serious drug interactions in this product, so it's important to check for conflicts with your medications.
Will this product work for skin conditions like eczema?
Licorice in Lappa is rated possibly effective for atopic dermatitis (eczema), and fennel and burdock are often used for skin health, but the evidence is limited or insufficient. Results vary, and you should talk with your doctor about whether it's right for your situation.
What are the most common side effects?
Licorice commonly causes headache, nausea, and vomiting. Butternut and acacia can cause diarrhea and digestive discomfort. Most people tolerate these herbs at food doses, but higher supplement amounts are more likely to cause problems.
Why does this product interact with so many medications?
Licorice, fennel, and acacia all affect how your liver processes drugs or how your body absorbs them, and several ingredients can affect electrolyte balance or blood clotting. Even a small liquid dose can carry these risks if you're on medications that depend on the same pathways.

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.

Lappa label
Go deeper

The Full Monographs Behind Lappa’s Ingredients

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

Herb & supplement monograph

Licorice

Interacts with 1,040 drugs

Licorice root is a traditional remedy used for sore throats, coughs, and digestive complaints, but solid human evidence is limited for most uses. Regular licorice contains glycyrrhizin, whic...

Read the full Licorice monograph → Herb & supplement monograph

Butternut

Interacts with 122 drugs

Butternut (Juglans cinerea) is a North American tree whose inner bark was traditionally used as a mild laxative and folk remedy. Modern scientific evidence supporting any of its uses is very...

Read the full Butternut monograph → Herb & supplement monograph

Fennel

Interacts with 740 drugs

Fennel is a Mediterranean herb widely used as a food and spice, and traditionally taken for digestive complaints, colic, and menstrual cramps. Some small studies suggest possible benefit for...

Read the full Fennel monograph → Herb & supplement monograph

Burdock

Interacts with 122 drugs

Burdock is a traditional herb most often used for skin problems and as a so-called 'blood purifier,' but high-quality human studies are lacking and most claims are not well proven. It is wid...

Read the full Burdock monograph → Herb & supplement monograph

Sarsaparilla

Interacts with 2 drugs

Sarsaparilla is a traditional root used in teas, tonics, and old-fashioned root beer flavoring. Modern evidence for its health claims is very limited and comes mostly from lab studies, so it...

Read the full Sarsaparilla monograph → Herb & supplement monograph

Thyme

Interacts with 379 drugs

Thyme is a common kitchen herb that has long been used for coughs, sore throats, and digestive complaints. It is generally safe in the amounts found in food, and some cough products that com...

Read the full Thyme monograph → Herb & supplement monograph

Gum Arabic

Interacts with 2,022 drugs

Gum arabic is a soluble dietary fiber from the acacia tree that is widely used as a safe food additive and is sometimes taken as a supplement for digestive health and as a prebiotic. Early s...

Read the full Gum Arabic monograph →
Sources

Sources & How We Checked

Lappa'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 152 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.

Licorice 92 references
  1. Farese RV Jr, Biglieri EG, Shackleton CH, et al. Licorice-induced hypermineralocorticoidism. N Engl J Med 1991;325:1223-7. PubMed
  2. Sigurjonsdottir HA, Ragnarsson J, Franzson L, Sigurdsson G. Is blood pressure commonly raised by moderate consumption of liquorice? J Hum Hypertens 1995;9:345-8.
  3. Armanini D, Lewicka S, Pratesi C, et al. Further studies on the mechanism of the mineralocorticoid action of licorice in humans. J Endocrinol Invest 1996;19:624-9. PubMed
  4. Zhang YD, Lorenzo B, Reidenberg MM. Inhibition of 11 beta hydroxysteroid dehydrogenase obtained from guinea pig kidney by furosemide, naringenin and some other compounds. J Steroid Biochem Mol Biol 1994;49:81-5.
  5. Strandberg TE, Jarvenpaa AL, Vanhanen H, McKeigue PM. Birth outcome in relation to licorice consumption during pregnancy. Am J Epidemiol 2001;153:1085-8. PubMed
  6. Sigurjonsdottir HA, Franzson L, Manhem K, et al. Liquorice-induced rise in blood pressure: a linear dose-response relationship. J Hum Hypertens 2001;15:549-52. PubMed
  7. Amato P, Christophe S, Mellon PL. Estrogenic activity of herbs commonly used as remedies for menopausal symptoms. Menopause 2002;9:145-50. PubMed
  8. Kent UM, Aviram M, Rosenblat M, Hollenberg PF. The licorice root derived isoflavan glabridin inhibits the activities of human cytochrome P450S 3A4, 2B6, and 2C9. Drug Metab Dispos 2002;30:709-15.. PubMed
  9. Yoshida S, Takayama Y. Licorice-induced hypokalemia as a treatable cause of dropped head syndrome. Clin Neurol Neurosurg 2003;105:286-7.. PubMed
  10. Strandberg TE, Andersson S, Jarvenpaa AL, et al. Preterm birth and licorice consumption during pregnancy. Am J Epidemiol 2002;156:803-5.. PubMed
  11. Hussain RM. The sweet cake that reaches parts other cakes can't! Postgrad Med J 2003;79:115-6.. PubMed
  12. Morris DJ, Davis E, Latif SA. Licorice, tobacco chewing, and hypertension. N Engl J Med 1990;322:849-50. PubMed
  13. Quinkler M, Stewart PM. Hypertension and the cortisol-cortisone shuttle. J Clin Endocrinol Metab 2003;88:2384-92. PubMed
  14. Westman EC, Guthrie GP. Licorice, tobacco chewing, and hypertension. N Engl J Med 1990;322:850. PubMed
  15. Mu Y, Zhang J, Zhang S, et al. Traditional Chinese medicines Wu Wei Zi (Schisandra chinensis Baill) and Gan Cao (Glycyrrhiza uralensis Fisch) activate pregnane X receptor and increase warfarin clearance in rats. J Pharmacol Exp Ther 2006;316:1369-77. PubMed
  16. Yasue H, Itoh T, Mizuno Y, Harada E. Severe hypokalemia, rhabdomyolysis, muscle paralysis, and respiratory impairment in a hypertensive patient taking herbal medicines containing licorice. Intern Med 2007;46:575-8. PubMed
  17. Brayley J, Jones J. Life-threatening hypokalemia associated with excessive licorice ingestion (letter). Am J Psychiatry 1994;151:617-8. PubMed
  18. de Klerk GJ, Nieuwenhuis G, Beutler JJ. Hypokalaemia and hypertension associated with use of liquorice flavoured chewing gum. BMJ 1997;314:731-2.
  19. Dellow EL, Unwin RJ, Honour JW. Pontefract cakes can be bad for you: refractory hypertension and liquorice excess. Nephol Dial Transplant 1999;14:218-20. PubMed
  20. Elinav E, Chajek-Shaul T. Licorice consumption causing severe hypokalemic paralysis. Mayo Clin Proc 2003;78:767-8. PubMed
  21. Eriksson JW, Carlberg B, Hillom V. Life-threatening ventricular tachycardia due to liquorice-induced hypokalemia. J Intern Med 1999;245:307-10.
  22. Janse A, van Iersel M, Hoefnagels WH, Olde Rikker MG. The old lady who liked liquorice: hypertension due to chronic intoxication in a memory-impaired patient. Neth J Med 2005;63:149-50.
  23. Lin SH, Yang SS, Chau T, Halperin ML. An unusual cause of hypokalemic paralysis: chronic licorice ingestion. Am J Med Sci 2003;325:153-6. PubMed
  24. van den Bosch AE, van der Klooster JM, Zuidgeest DM, et al. Severe hypokalemic paralysis and rhabdomyolysis due to ingestion of liquorice. Neth J Med 2005;63:146-8.
  25. van Uum SH. Liquorice and hypertension. Neth J Med 2005;63:119-20.
  26. Russo S, Mastropasqua M, Mosetti MA, et al. Low doses of liquorice can induce hypertension encephalopathy. Am J Nephrol 2000;20:145-8. PubMed
  27. Stormer FC, Reistad R, Alexander J. Glycyrrhizic acid in liquorice - evaluation of health hazard. Food Chem Toxicol 1993;31:303-12. PubMed
  28. Sontia B, Mooney J, Gaudet L, Touyz RM. Pseudohyperaldosteronism, liquorice, and hypertension. J Clin Hypertens (Greenwich) 2008;10:153-7. PubMed
  29. Francini-Pesenti F, Puato M, Piccoli A, Brocadello F. Liquorice-induced hypokalaemia and water retention in the absence of hypertension. Phytother Res 2008;22:563-5. PubMed
  30. Lapi F, Gallo E, Bernasconi S, et al. Myopathies associated with red yeast rice and liquorice: spontaneous reports from the Italian Surveillance System of Natural Health Products. Br J Clin Pharmacol 2008;66:572-4. PubMed
  31. Chen MF, Shimada F, Kato H, Yano S, Kanaoka M. Effect of glycyrrhizin on the pharmacokinetics of prednisolone following low dosage of prednisolone hemisuccinate. Endocrinol Jpn 1990;37:331-41. PubMed
  32. Teelucksingh S, Mackie AD, Burt D, McIntyre MA, Brett L, Edwards CR. Potentiation of hydrocortisone activity in skin by glycyrrhetinic acid. Lancet 1990;335(8697):1060-3. PubMed
  33. Heidemann HT, Kreuzfelder E. Hypokalemic rhabdomyolysis with myoglobinuria due to licorice ingestion and diuretic treatment. Klin Wochenschr 1983;61:303-5. PubMed
  34. Hukkanen J, Ukkola O, Savolainen MJ. Effects of low-dose liquorice alone or in combination with hydrochlorothiazide on the plasma potassium in healthy volunteers. Blood Press 2009;18:192-5. PubMed
  35. Bisogni V, Rossi GP, Calò LA. Apparent mineralcorticoid excess syndrome, an often forgotten or unrecognized cause of hypokalemia and hypertension: case report and appraisal of the pathophysiology. Blood Press. 2014 Jun;23(3):189-92. PubMed
  36. Dehours E, Vallé B, Rougé-Bugat ME, Florent B, Bounes V, Franchitto N. Suspected hypokalaemia following liquorice ingestion on board ship. J Telemed Telecare. 2013 Jun;19(4):227-8. PubMed
  37. Kormann R, Languille E, Amiot HM, Hertig A. Dying for a cup of tea. BMJ Case Rep. 2012 Oct 19;2012. PubMed
  38. Panduranga P, Al-Rawahi N. Licorice-induced severe hypokalemia with recurrent torsade de pointes. Ann Noninvasive Electrocardiol. 2013 Nov;18(6):593-6. PubMed
  39. Räikkönen K, Seckl JR, Heinonen K, Pyhälä R, Feldt K, Jones A, Pesonen AK, Phillips DI, Lahti J, Järvenpää AL, Eriksson JG, Matthews KA, Strandberg TE, Kajantie E. Maternal prenatal licorice consumption alters hypothalamic-pituitary-adrenocortical axis fu
  40. Robles BJ, Sandoval AR, Dardon JD, Blas CA. Lethal liquorice lollies (liquorice abuse causing pseudohyperaldosteronism). BMJ Case Rep. 2013 Sep 19;2013. PubMed
  41. Chamberlain, J. J. and Abolnik, I. Z. Pulmonary edema following a licorice binge. West J Med 1997;167(3):184-185.
  42. Barrella, M., Lauria, G., Quatrale, R., and Paolino, E. Hypokaliemic rhabdomyolysis associated with liquorice ingestion: report of an atypical case. Ital.J Neurol.Sci 1997;18(4):217-220. PubMed
  43. Fugh-Berman, A. Herb-drug interactions. Lancet 2000;355(9198):134-138. PubMed
  44. Hasegawa, J., Suyama, Y., Kinugawa, T., Morisawa, T., and Kishimoto, Y. Echocardiographic findings of the heart resembling dilated cardiomyopathy during hypokalemic myopathy due to licorice-induced pseudoaldosteronism. Cardiovasc.Drugs Ther 1998;12(6):59 PubMed
  45. van Rossum, T. G., Vulto, A. G., Hop, W. C., Brouwer, J. T., Niesters, H. G., and Schalm, S. W. Intravenous glycyrrhizin for the treatment of chronic hepatitis C: a double-blind, randomized, placebo-controlled phase I/II trial. J Gastroenterol Hepatol 199 PubMed
  46. Lozano, P., Flores, D., Martinez, S., Artigues, I., Rimbau, E. M., and Gomez, F. Upper limb ischemia induced by chronic licorice ingestion. J Cardiovasc.Surg (Torino) 2000;41(4):631-632.
  47. Brouwers, A. J. and van der, Meulen J. ['Licorice hypertension' also caused by licorice tea]. Ned.Tijdschr Geneeskd. 4-14-2001;145(15):744-747.
  48. van Rossum, T. G., Vulto, A. G., Hop, W. C., and Schalm, S. W. Glycyrrhizin-induced reduction of ALT in European patients with chronic hepatitis C. Am J Gastroenterol 2001;96(8):2432-2437. PubMed
  49. Sigurjonsdottir, H. A., Manhem, K., Axelson, M., and Wallerstedt, S. Subjects with essential hypertension are more sensitive to the inhibition of 11 beta-HSD by liquorice. J Hum Hypertens 2003;17(2):125-131.
  50. Shintani, S., Murase, H., Tsukagoshi, H., and Shiigai, T. Glycyrrhizin (licorice)-induced hypokalemic myopathy. Report of 2 cases and review of the literature. Eur Neurol 1992;32(1):44-51. PubMed
  51. Chen, M. F., Shimada, F., Kato, H., Yano, S., and Kanaoka, M. Effect of oral administration of glycyrrhizin on the pharmacokinetics of prednisolone. Endocrinol Jpn 1991;38(2):167-174. PubMed
  52. Lee, C. K., Park, K. K., Lim, S. S., Park, J. H., and Chung, W. Y. Effects of the licorice extract against tumor growth and cisplatin-induced toxicity in a mouse xenograft model of colon cancer. Biol Pharm Bull 2007;30(11):2191-2195. PubMed
  53. Isaia, G. C., Pellissetto, C., Ravazzoli, M., and Tamone, C. Acute adrenal crisis and hypercalcemia in a patient assuming high liquorice doses. Minerva Med 2008;99(1):91-94.
  54. Bocker, D. and Breithardt, G. [Induction of arrhythmia by licorice abuse]. Z Kardiol 1991;80(6):389-391.
  55. Tacconi, P., Paribello, A., Cannas, A., and Marrosu, M. G. Carpal tunnel syndrome triggered by excessive licorice consumption. J Peripher.Nerv.Syst. 2009;14(1):64-65. PubMed
  56. Tu, J. H., He, Y. J., Chen, Y., Fan, L., Zhang, W., Tan, Z. R., Huang, Y. F., Guo, D., Hu, D. L., Wang, D., and Hong-Hao Zhou. Effect of glycyrrhizin on the activity of CYP3A enzyme in humans. Eur J Clin Pharmacol 2010;66(8):805-810. PubMed
  57. Goultschin, J., Palmon, S., Shapira, L., Brayer, L., and Gedalia, I. Effect of glycyrrhizin-containing toothpaste on dental plaque reduction and gingival health in humans. A pilot study. J Clin Periodontol 1991;18(3):210-212. PubMed
  58. Scali, M., Pratesi, C., Zennaro, M. C., Zampollo, V., and Armanini, D. Pseudohyperaldosteronism from liquorice-containing laxatives. J Endocrinol Invest 1990;13(10):847-848. PubMed
  59. Chatterjee, N., Domoto-Reilly, K., Fecci, P. E., Schwamm, L. H., and Singhal, A. B. Licorice-associated reversible cerebral vasoconstriction with PRES. Neurology 2010;75(21):1939-1941. PubMed
  60. Imtiaz, K. E. Sweet root, bitter pill: liquorice-induced hyperaldosteronism. QJM 2011;104(12):1093-1095. PubMed
  61. van Beers, E. J., Stam, J., and van den Bergh, W. M. Licorice consumption as a cause of posterior reversible encephalopathy syndrome: a case report. Crit Care 2011;15(1):R64. PubMed
  62. MacKenzie, M. A., Hoefnagels, W. H., Jansen, R. W., Benraad, T. J., and Kloppenborg, P. W. The influence of glycyrrhetinic acid on plasma cortisol and cortisone in healthy young volunteers. J Clin Endocrinol Metab 1990;70(6):1637-1643. PubMed
  63. Bardhan, K. D., Cumberland, D. C., Dixon, R. A., and Holdsworth, C. D. Clinical trial of deglycyrrhizinised liquorice in gastric ulcer. Gut 1978;19(9):779-782. PubMed
  64. Koster, M. and David, G. K. Reversible severe hypertension due to licorice ingestion. N Engl J Med 1968;278(25):1381-1383. PubMed
  65. Corse, F. M., Galgani, S., Gasparini, C., Giacanelli, M., and Piazza, G. Acute hypokalemic myopathy due to chronic licorice ingestion: report of a case. Ital J Neurol Sci 1983;4(4):493-497. PubMed
  66. Berlango Jimenez A., Jimenez Murillo L., Montero Perez F. J., Munoz Avila J. A., Torres Murillo J., and Calderon de la Barca Gazquez J. M. [Acute rhabdomyolysis and tetraparesis secondary to hypokalemia due to ingested licorice]. An Med Interna 1995;12(1)
  67. Bernardi, M., D'Intino, P. E., Trevisani, F., Cantelli-Forti, G., Raggi, M. A., Turchetto, E., and Gasbarrini, G. Effects of prolonged ingestion of graded doses of licorice by healthy volunteers. Life Sci 1994;55(11):863-872. PubMed
  68. van der Zwan A. Hypertension encephalopathy after liquorice ingestion. Clin Neurol Neurosurg 1993;95(1):35-37. PubMed
  69. Werner, S., Brismar, K., and Olsson, S. Hyperprolactinaemia and liquorice. Lancet 2-10-1979;1(8111):319.
  70. Nishioka, K. and Seguchi, T. Contact allergy due to oil-soluble licorice extracts in cosmetic products. Contact Dermatitis 1999;40(1):56. PubMed
  71. Yoshino T, Yanagawa T, Watanabe K. Risk factors for pseudoaldosteronism with rhabdomyolysis caused by consumption of drugs containing licorice and differences between incidence of these conditions in Japan and other countries: case report and literature r
  72. Li G, Simmler C, Chen L, et al. Cytochrome P450 inhibition by three licorice species and fourteen licorice constituents. Eur J Pharm Sci. 2017;109:182-190. PubMed
  73. Li J, Fan X, Wang Q. Hypertensive crisis with 2 target organ impairment induced by glycyrrhizin: a case report. Medicine (Baltimore) 2018;97(11):e0073. PubMed
  74. Foster CA, Church KS, Poddar M, Van Uum SH, Spaic T. Licorice-induced hypertension: a case of pseudohyperaldosteronism due to jelly bean ingestion. Postgrad Med 2017;129(3):329-31. PubMed
  75. Gallacher SD, Tsokolas G, Dimitropoulos I. Liquorice-induced apparent mineralocorticoid excess presenting in the emergency department. Clin Med (Lond) 2017;17(1):43-5. PubMed
  76. Dai DW, Singh I, Hershman JM. Lozenge-induced hypermineralcorticoid state--a unique case of licorice lozenges resulting in hypertension and hypokalemia. J Clin Hypertens (Greenwich) 2016;18(2):159-60.
  77. O'Connell K, Kinsella J, McMahon C, Holian J, O'Riordan S. Posterior reversible encephalopathy syndrome (PRES) associated with liquorice consumption. Ir J Med Sci 2016;185(4):945-7. PubMed
  78. Hataya Y, Oba A, Yamashita T, Komatsu Y. Hyponatremia in an elderly patient due to isolated hypoaldosteronism occurring after licorice withdrawal. Intern Med 2017;56(2):175-9. PubMed
  79. Ha Y, Wang T, Li J, et al. Herb-Drug Interaction Potential of Licorice Extract and Paclitaxel: A Pharmacokinetic Study in Rats. Eur J Drug Metab Pharmacokinet. 2020;45(2):257-264. PubMed
  80. Edelman ER, Butala NM, Avery LL, Lundquist AL, Dighe AS. Case 30-2020: A 54-Year-Old Man with Sudden Cardiac Arrest. N Engl J Med. 2020;383(13):1263-1275. PubMed
  81. Wang H, Dong L, Qu F, et al. Effects of glycyrrhizin on the pharmacokinetics of nobiletin in rats and its potential mechanism. Pharm Biol. 2020 Dec;58(1):352-356. PubMed
  82. Attou R, Redant S, Honore PM, Preseau T, Hantson P, De Bels D. Liquorice intoxication can lead to cardiac arrest! Case Rep Emerg Med. 2020;2020:3727682. PubMed
  83. Benge E, Shah P, Yamaguchi L, Josef V. Trick or Treat? Licorice-Induced Hypokalemia: A Case Report. Cureus 2020;12(11):e11656. PubMed
  84. Abe K, Higurashi T, Takahashi M, et al. Concomitant Use of High-dose Methotrexate and Glycyrrhizin Affects Pharmacokinetics of Methotrexate, Resulting in Hepatic Toxicity. In Vivo 2021;35(4):2163-2169. PubMed
  85. Awad N, Makar G, Burroughs V, Ravi P, Burroughs SR. Licorice-induced apparent mineralocorticoid excess causing persistent hypertension and hypokalemia. Acta Endocrinol (Buchar) 2020;16(4):508-510. PubMed
  86. Patel P, Aknouk M, Dawson A, et al. How Much Is Too Much? Exploring Pseudohyperaldosteronism in Glycyrrhizic Acid Toxicity From Chronic Licorice Root Consumption. Cureus 2021;13(7):e16454. PubMed
  87. Fan ZJ, Liu JM, Li XX, et al. Glycyrrhizin-Induced Pseudohyperaldosteronism: A Case Report. Chin J Integr Med 2022. PubMed
  88. Gatica-Ortega ME, Pastor-Nieto MA. Allergic contact dermatitis to Glycyrrhiza inflata root extract in an anti-acne cosmetic product. Contact Dermatitis 2021;85(4):454-455.
  89. Wang JB, Huang A, Wang Y, et al. Corticosteroid plus glycyrrhizin therapy for chronic drug- or herb-induced liver injury achieves biochemical and histological improvements: a randomised open-label trial. Aliment Pharmacol Ther 2022;55(10):1297-1310. PubMed
  90. 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
  91. 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
  92. Han EJ, Park JS. Lethal Arrhythmia Induced by Licorice. J Korean Med Sci 2023;38(12):e107. PubMed

See these in context on the Licorice monograph →

Butternut 3 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. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.

See these in context on the Butternut monograph →

Fennel 17 references
  1. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
  2. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  3. Zhu M, Wong PY, Li RC. Effect of oral administration of fennel (Foeniculum vulgare) on ciprofloxacin absorption and disposition in the rat. J Pharm Pharmacol 1999;51:1391-6.
  4. Gral N, Beani JC, Bonnot D, et al. [Plasma levels of psoralens after celery ingestion]. Ann Dermatol Venereol 1993;120:599-603.
  5. Burkhard PR, Burkhardt K, Haenggeli CA, Landis T. Plant-induced seizures: reappearance of an old problem. J Neurol 1999;246:667-70. PubMed
  6. Rosti L, Nardini A, Bettinelli ME, Rosti D. Toxic effects of a herbal tea mixture in two newborns. Acta Paediatrica 1994;83:683. PubMed
  7. Cuzzolin L, Zaffani S, and Benoni G. Safety implications regarding use of phytomedicines. Eur.J Clin Pharmacol. 2006;62:37-42. PubMed
  8. Tognolini, M., Ballabeni, V., Bertoni, S., Bruni, R., Impicciatore, M., and Barocelli, E. Protective effect of Foeniculum vulgare essential oil and anethole in an experimental model of thrombosis. Pharmacol.Res 2007;56(3):254-260. PubMed
  9. Subehan, Usia, T., Iwata, H., Kadota, S., and Tezuka, Y. Mechanism-based inhibition of CYP3A4 and CYP2D6 by Indonesian medicinal plants. J Ethnopharmacol. 5-24-2006;105(3):449-455. PubMed
  10. Tognolini, M., Barocelli, E., Ballabeni, V., Bruni, R., Bianchi, A., Chiavarini, M., and Impicciatore, M. Comparative screening of plant essential oils: phenylpropanoid moiety as basic core for antiplatelet activity. Life Sci. 2-23-2006;78(13):1419-1432. PubMed
  11. Subehan, Zaidi, S. F., Kadota, S., and Tezuka, Y. Inhibition on human liver cytochrome P450 3A4 by constituents of fennel (Foeniculum vulgare): identification and characterization of a mechanism-based inactivator. J Agric.Food Chem. 12-12-2007;55(25):101 PubMed
  12. LEVY, S. B. Bronchial asthma due to ingestion of fennel and fennel seed. Ann.Allergy 1948;6(4):415.
  13. Ottolenghi, A., De Chiara, A., Arrigoni, S., Terracciano, L., and De Amici, M. [Diagnosis of food allergy caused by fruit and vegetables in children with atopic dermatitis]. Pediatr Med Chir 1995;17(6):525-530.
  14. Trabace L, Tucci P, Ciuffreda L, et al. "Natural" relief of pregnancy-related symptoms and neonatal outcomes: above all do no harm. J Ethnopharmacol. 2015;174:396-402. PubMed
  15. Denaxa D, Arkwright PD. Fennel as a cause of immediate hypersensitivity to toothpaste. Ann Allergy Asthma Immunol. 2020;125(1):99-100. PubMed
  16. Lee HW, Ang L, Lee MS, Alimoradi Z, Kim E. Fennel for reducing pain in primary dysmenorrhea: a systematic review and meta-analysis of randomized controlled trials. Nutrients 2020;12(11):3438. PubMed
  17. Mathew T, John SK, Javali M, Vasireddy M, Nadig R, Sarma GRK. Substance use related cluster headache: A case series. Headache 2022;62(7):908-910. PubMed

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Burdock 11 references
  1. Iwakami S, Wu JB, Ebizuka Y, Sankawa U. Platelet activating factor (PAF) antagonists contained in medicinal plants: lignans and sesquiterpenes. Chem Pharm Bull (Tokyo) 1992;40:1196-8. PubMed
  2. Sasaki Y, Kimura Y, Tsunoda T, Tagami H. Anaphylaxis due to burdock. Int J Dermatol 2003;42:472-3. PubMed
  3. Rhoads PM, Tong TG, Banner W Jr, Anderson R. Anticholinergic poisonings associated with commercial burdock root tea. J Toxicol Clin Toxicol 1984-85;22:581-4. PubMed
  4. Rodriguez P, Blanco J, Juste S, et al. Allergic contact dermatitis due to burdock (Arctium lappa). Contact Dermatitis 1995;33:134-5.
  5. Kassler, W. J., Blanc, P., and Greenblatt, R. The use of medicinal herbs by human immunodeficiency virus-infected patients. Arch Intern Med 1991;151(11):2281-2288. DOI
  6. Chan, Y. S., Cheng, L. N., Wu, J. H., Chan, E., Kwan, Y. W., Lee, S. M., Leung, G. P., Yu, P. H., and Chan, S. W. A review of the pharmacological effects of Arctium lappa (burdock). Inflammopharmacology. 2011;19(5):245-254. PubMed
  7. Breed, F. B. and Kuwabara, T. Burdock ophthalmia. Arch Ophthalmol 1966;75(1):16-20.
  8. Bryson, P. D., Watanabe, A. S., Rumack, B. H., and Murphy, R. C. Burdock root tea poisoning. Case report involving a commercial preparation. JAMA 5-19-1978;239(20):2157. DOI
  9. <p>Fletcher GF<span>, </span>Cantwell JD. Burdock root tea poisoning. JAMA <span>1978 Oct 6;240(15):1586.</span></p> DOI
  10. Latif A, Fichadiya H, Abid F, Capo G. Herbal Teas and Thrombocytopenia: A Curious Case of Yellow Dock and Burdock-Induced Thrombocytopenia. Eur J Case Rep Intern Med 2022;9(3):003247. PubMed
  11. Niazi B, Ahmed K, Ahmed M, Ali S, Song K, Elias S. Drug-Induced Liver Injury from Herbal Liver Detoxification Tea. Case Rep Gastroenterol 2022;16(3):612-617. PubMed

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Sarsaparilla 3 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. 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. Vandenplas O, Depelchin S, Toussaint G, et al. Occupational asthma caused by sarsaparilla root dust. J Allergy Clin Immunol 1996;97:1416-8. PubMed

See these in context on the Sarsaparilla monograph →

Thyme 18 references
  1. Zava DT, Dollbaum CM, Blen M. Estrogen and progestin bioactivity of foods, herbs, and spices. Proc Soc Exp Biol Med 1998;217:369-78. PubMed
  2. Electronic Code of Federal Regulations. Title 21. Part 182 -- Substances Generally Recognized As Safe. Available at: https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?CFRPart=182
  3. Okazaki K, Kawazoe K, Takaishi Y. Human platelet aggregation inhibitors from thyme (Thymus vulgaris L.). Phytother Res 2002;16:398-9. .
  4. Spiewak R, Skorska C, Dutkiewicz J. Occupational airborne contact dermatitis caused by thyme dust. Contact Dermatitis 2001;44:235-9. . PubMed
  5. Ernst E, Marz R, Sieder C. A controlled multi-centre study of herbal versus synthetic secretolytic drugs for acute bronchitis. Phytomedicine 1997;4:287-93. PubMed
  6. Yamamoto J, Yamada K, Naemura A, et al. Testing various herbs for antithrombotic effect. Nutrition 2005;21(5):580-7. PubMed
  7. Tognolini, M., Barocelli, E., Ballabeni, V., Bruni, R., Bianchi, A., Chiavarini, M., and Impicciatore, M. Comparative screening of plant essential oils: phenylpropanoid moiety as basic core for antiplatelet activity. Life Sci. 2-23-2006;78(13):1419-1432. PubMed
  8. Mackiewicz, B., Skorska, C., Dutkiewicz, J., Michnar, M., Milanowski, J., Prazmo, Z., Krysinska-Traczyk, E., and Cisak, E. Allergic alveolitis due to herb dust exposure. Ann Agric Environ Med 1999;6(2):167-170.
  9. Martinez-Gonzalez, M. C., Goday Bujan, J. J., Martinez, Gomez W., and Fonseca, Capdevila E. Concomitant allergic contact dermatitis due to Rosmarinus officinalis (rosemary) and Thymus vulgaris (thyme). Contact Dermatitis 2007;56(1):49-50.
  10. Jukic, M., Politeo, O., Maksimovic, M., Milos, M., and Milos, M. In vitro acetylcholinesterase inhibitory properties of thymol, carvacrol and their derivatives thymoquinone and thymohydroquinone. Phytother.Res 2007;21(3):259-261.
  11. Marzian, O. [Treatment of acute bronchitis in children and adolescents. Non-interventional postmarketing surveillance study confirms the benefit and safety of a syrup made of extracts from thyme and ivy leaves]. MMW.Fortschr.Med 6-28-2007;149(27-28 Suppl
  12. Cuzzolin, L. and Benoni, G. Attitudes and knowledge toward natural products safety in the pharmacy setting: an Italian study. Phytother.Res 2009;23(7):1018-1023. PubMed
  13. Berova, N., Stransky, L., and Krasteva, M. Studies on contact dermatitis in stomatological staff. Dermatol.Monatsschr. 1990;176(1):15-18.
  14. Smeenk, G., Kerckhoffs, H. P., and Schreurs, P. H. Contact allergy to a reaction product in Hirudoid cream: an example of compound allergy. Br.J Dermatol. 1987;116(2):223-231.
  15. Le Roy, R., Grosshans, E., and Foussereau, J. [Investigation of contact allergies in 100 cases of ulcus cruris (author's transl)]. Derm.Beruf.Umwelt. 1981;29(6):168-170.
  16. Lorenzi, S., Placucci, F., Vincenzi, C., Bardazzi, F., and Tosti, A. Allergic contact dermatitis due to thymol. Contact Dermatitis 1995;33(6):439-440. PubMed
  17. Bahadoran P, Rokni FK, Fahami F. Investigating the therapeutic effect of vaginal cream containing garlic and thyme compared to clotrimazole cream for the treatment of mycotic vaginitis. Iran J Nurs Midwifery Res 2010;15(Suppl 1):343-9.
  18. Erol S, Aydin B, Dilli D, Okumus N, Zenciroglu A, Gündüz M. An interesting newborn case of fructose 1-6 diphosphatase deficiency triggered after thyme juice ingestion. Clin Lab. 2014;60(1):151-3. PubMed

See these in context on the Thyme monograph →

Gum Arabic 8 references
  1. Jensen CD, Spiller GA, Gates JE, et al. The effect of acacia gum and a water-soluble dietary fiber mixture on blood lipids in humans. J Am Coll Nutr 1993;12:147-54. PubMed
  2. Eltayeb IB, Awad AI, Elderbi MA, Shadad SA. Effect of gum arabic on the absorption of a single oral dose of amoxicillin in healthy Sudanese volunteers. J Antimicrob Chemother 2004;54:577-8. PubMed
  3. Babiker R, Merghani TH, Elmusharaf K, et al. Effects of gum Arabic ingestion on body mass index and body fat percentage in healthy adult females: two-arm randomized, placebo controlled, double-blind trial. Nutr J 2012;11:111. PubMed
  4. Babiker R, Elmusharaf K, Keogh MB, Banaga AS, Saeed AM. Metabolic effect of gum Arabic (Acacia senegal) in patients with type 2 diabetes mellitus (T2DM): randomized, placebo controlled double blind trial. Functional Foods in Health and Disease. 2017;7(3): DOI
  5. Beneke CE, Viljoen AM, Hamman JH. Polymeric plant-derived excipients in drug delivery. Molecules. 2009;14(7):2602-20. PubMed
  6. Ali NE, Kaddam LA, Alkarib SY, et al. Gum Arabic (Acacia Senegal) Augmented Total Antioxidant Capacity and Reduced C-Reactive Protein among Haemodialysis Patients in Phase II Trial. Int J Nephrol. 2020;2020:7214673.
  7. Mortensen A, Aguilar F, Crebelli R, et al. Re-evaluation of acacia gum (E 414) as a food additive. EFSA J. 2017;15(4):e04741. PubMed
  8. Larson R, Nelson C, Korczak R, et al. Acacia Gum Is Well Tolerated While Increasing Satiety and Lowering Peak Blood Glucose Response in Healthy Human Subjects. Nutrients 2021;13(2):618. PubMed

See these in context on the Gum Arabic 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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