Interactions on record — worth a quick check against your medications. Based on 6 of 9 ingredients. Check your meds →
Dietary supplement

Throat Shield Ingredients & Drug Interactions

by Gaia Herbs

Throat Shield label
See full label image
Other (e.g. Tea Bag) Category: Botanical
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Throat Shield 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

Throat Shield is a dietary supplement by Gaia Herbs with 9 active ingredients. Its ingredients are commonly taken for constipation, diarrhea, high cholesterol.Based on those ingredients, 2,179 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Marshmallow, Dietary Fiber, Sage. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Throat Shield by Gaia Herbs

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

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HelloPharmacist Scorecard of Throat Shield by Gaia Herbs

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 11, 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.
  • No proprietary blends here — you can verify the dose of every single component.

Throat Shield contains 8 active ingredients. The main players are peppermint (leaf and essential oil), sage (leaf and essential oil), fennel, marshmallow root, licorice root, and grindelia.

Peppermint and sage are the aromatic oils; fennel, marshmallow, and licorice bring a soothing, demulcent quality. There are no inactive ingredients listed.

Does it work?

Not established
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
Not established

The graded evidence we hold for these ingredients covers different conditions than the ones this product is marketed for, so there's no established rating for its stated use.

Why this rating?
  • The label markets this product for: Supports throat hydration and immune health.
  • We looked for evidence on: Cough, Common cold, Dry mouth, Throat irritation, Laryngitis, Pharyngitis — and 1 related terms.
  • The closest evidence on file: Fennel is rated "Insufficient Reliable Evidence To Rate" for Cough (Natural Medicines).
  • Also on file: Sage is rated "Insufficient Reliable Evidence To Rate" for Dry mouth, Pharyngitis.
  • Also on file: Peppermint is rated "Insufficient Reliable Evidence To Rate" for Common cold.

The evidence is mixed depending on what you're taking it for. Peppermint is likely effective for irritable bowel syndrome and possibly effective for indigestion and nausea from chemotherapy.

Sage is possibly effective for menopausal symptoms and cognitive function. Licorice is possibly effective for eczema and canker sores.

Fennel is possibly effective for period pain, but the evidence for its other uses — anxiety, bronchitis, bedwetting — is insufficient. Marshmallow's effectiveness for sore throats or respiratory issues isn't established in our data.

Grindelia we cannot assess.

The evidence, ingredient by ingredient Black Psyllium Peppermint Sage Fennel Marshmallow Licorice

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.

Peppermint and sage are generally well tolerated in tea form, though both can cause abdominal pain, nausea, or diarrhea orally. Concentrated oils carry more risk — peppermint oil in large amounts may cause chemical burns in the mouth and throat.

A rare allergic reaction (anaphylaxis) has been reported with peppermint candy. Sage in large doses has caused seizures due to its thujone content.

Fennel is usually well tolerated but can trigger gastrointestinal upset or allergic reactions; seizures are rare. Licorice in small food amounts is fine, but medicinal amounts can cause headache, nausea, and serious effects (low potassium, high blood pressure) with long-term use.

Marshmallow data are limited — safety in pregnancy and lactation is not established.

Side effects, ingredient by ingredient Black Psyllium Peppermint Sage Fennel Marshmallow Licorice

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?
  • 6 of the 6 matched ingredients can interact with medications — Black Psyllium, Fennel, Sage, Peppermint, Marshmallow, among others.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; seizure medications; immunosuppressants / transplant drugs; diabetes medications; heart-rhythm medications; lithium.
  • For scale: 2,180 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.

Check with your pharmacist before using this if you take: drugs broken down by CYP3A4, CYP2C9, or CYP2C19 enzymes (a long list including some blood pressure meds, some statins, some antidepressants); heart medications like digoxin; blood thinners such as warfarin; cyclosporine (an immunosuppressant); birth control pills or hormone therapy; sedatives or CNS depressants; blood pressure medications; or chemotherapy drugs like cisplatin or paclitaxel. Grindelia was not checked.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with no established evidence rating for its marketed use. Moderate medication interactions have been identified, and safety information is well characterized.

This is a traditional throat-soothing blend with decent evidence for some uses (peppermint for IBS, licorice for canker sores). But it's not a simple product — it has real interactions with many medications, especially liver-metabolized drugs, blood thinners, and heart meds.

If you take any prescription drugs or have high blood pressure, heart issues, or bleeding disorders, talk to your pharmacist or doctor before using it.

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

Assessment coverage: 8 of 9 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Nov 20, 2017.

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 Throat Shield, straight from the product label.

Brand Gaia Herbs
Barcode (UPC) 751063145909
Net contents 16 Tea Bag(s); 1.02 oz.; 28.8 Gram(s)
Market status On market
Date entered into DSLD Nov 20, 2017
DSLD ID 80829
Product type Botanical
Supplement form Other (e.g. Tea Bag)
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Organic
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 Throat Shield by Gaia Herbs, 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:
1 Tea Bag(s)
Maximum serving Sizes:
1 Tea Bag(s)
Servings per container
16
UPC/BARCODE
751063145909
IngredientAmount% DV
Dietary Fiber1 Gram(s)3%
Grindelia216 mg--
Peppermint540 mg--
Sage225 mg--
Fennel225 mg--
Marshmallow180 mg--
Licorice396 mg--
Peppermint leaf essential oil14 mg--
Sage leaf essential oil4 mg--

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.
General

C24020 [005] 863-0217

General Statements

Aboca code

Steeped in a healthy lifestyle Our mission has remained unchanged for nearly 30 years—offer the highest quality herbal supplements to support your health. One satisfying way of including herbs in daily life is through the ritual of drinking tea. Our respect for this ancient practice is reflected in the quality of our herbs and in tea bags which use no staples or glue.

A partnership of mutual beliefs This tea is produced in Tuscany, Italy by Aboca, the herbal supplement leader in more than 25,000 European pharmacies and health food stores since 1978. Gaia Herbs’ partnership with Aboca is born from a mutual belief in sustainable product development, dedication to quality, and a deep respect for science and nature working in harmony. Aboca

Soothing comfort

Supports throat hydration & immune health

16 (1.8 g) tea bags

Product of Italy

Nourish your throat & voice

Track the life story of each herb in your tea by entering its ID# at GaiaHerbs.com

Formula

Sage

With soothing Marshmallow and Sage leaf, this cooling tea helps maintain the normal protective lining of the throat by providing hydration and immune support. Essential oils of Peppermint and Sage tingle and invigorate.

Seals/Symbols

USDA Organic

FDA Statement of Identity

Herbal Dietary Supplement

Formulation

Caffeine-free

Certified Organic by Oregon Tilth.

FDA Disclaimer Statement

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

Brand IP Statement(s)

The silky texture of Throat Shield tea preserves your voice and blankets your throat during times when your body’s defenses are challenged.

meetyourherbs

Suggested/Recommended/Usage/Directions

Directions Adults pour one cup of freshly boiled water over tea bag and steep, covered, for 10 minutes. Drink once daily as needed. For added support, combine this tea with Throat Shield lozenges or spray.

Precautions

If you have a medical condition or take medications, please consult with your doctor before using this product. Licorice should not be taken if you have kidney or liver disease, hypertension, edema, excessive potassium depletion or during pregnancy. Consult with your practitioner if breast-feeding.

Licorice should not be taken if you have kidney or liver disease, hypertension, edema, excessive potassium depletion or during pregnancy.

Keep away from children.

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

See for yourself

Throat Shield by Gaia Herbs label

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

Throat Shield 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 Throat Shield by Gaia Herbs

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

Serving size1 Tea Bag(s) Dosage formOther (e.g. Tea Bag) Servings per container16 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.

Dietary Fiber

Interacts with
2,025 drugs
1 Gram(s) per serving

Black psyllium is a soluble-fiber supplement made from the seeds of a Plantago plant, used mostly to ease constipation and support digestive health. I...

Dietary Fiber monograph & interactions

Grindelia

216 mg per serving

Peppermint

Interacts with
796 drugs
540 mg per serving

Peppermint is a popular herb with the best evidence supporting enteric-coated peppermint oil for easing IBS symptoms. It is generally well tolerated f...

Peppermint monograph & interactions

Sage

Interacts with
1,296 drugs
225 mg per serving

Sage is a common kitchen herb that is generally safe in food amounts and is traditionally used for sore throats, digestion, sweating, and memory. Some...

Sage monograph & interactions

Fennel

Interacts with
740 drugs
225 mg per serving

Fennel is a Mediterranean herb widely used as a food and spice, and traditionally taken for digestive complaints, colic, and menstrual cramps. Some sm...

Fennel monograph & interactions

Marshmallow

Interacts with
2,040 drugs
180 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,...

Marshmallow monograph & interactions

Licorice

Interacts with
1,040 drugs
396 mg per serving

Licorice root is a traditional remedy used for sore throats, coughs, and digestive complaints, but solid human evidence is limited for most uses. Regu...

Licorice monograph & interactions

Peppermint leaf essential oil

Interacts with
796 drugs
14 mg per serving

Peppermint is a popular herb with the best evidence supporting enteric-coated peppermint oil for easing IBS symptoms. It is generally well tolerated f...

Peppermint leaf essential oil monograph & interactions

Sage leaf essential oil

Interacts with
1,296 drugs
4 mg per serving

Sage is a common kitchen herb that is generally safe in food amounts and is traditionally used for sore throats, digestion, sweating, and memory. Some...

Sage leaf essential oil monograph & interactions
Interaction report

Throat Shield by Gaia Herbs Drug Interactions

Want to check YOUR meds against Throat Shield?

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
2,179Drugs
1,368 Moderate 811 Minor

Ingredients driving the most interactions

Marshmallow 2,040
Dietary Fiber 2,025
Sage 1,296
Licorice 1,040
Peppermint 796

Individual Drug Interactions

The ingredients in Throat Shield interact with 2,179 drugs. Click any drug to see the details.

6 of the 9 ingredients in Throat Shield interact with drugs. Each result below shows which ingredient is responsible. Marshmallow Dietary Fiber Sage Licorice Peppermint Fennel

Each ingredient & the kinds of drugs it affects

For each ingredient in Throat Shield 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.

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
Marshmallow full monograph & interactions

Dietary Fiber7 drug types · 2,025 drugs

Carbamazepine (Tegretol)

Theoretically, black psyllium might reduce the effects of carbamazepine and increase the risk for convulsions.
Theoretically, black psyllium might reduce carbamazepine absorption. A preliminary study using blond psyllium reported decreased carbamazepine bioavailability due to binding of the drug to psyllium, as well as reduction of available fluid in the gut for dissolution of the drug. This interaction may also occur with black psyllium.

Likelihood Probable Evidence D
Lithium

Theoretically, taking black psyllium at the same time as lithium might reduce lithium absorption.
The fiber in black psyllium might reduce lithium absorption and plasma levels. Some case reports describe a reduction in plasma lithium levels with concomitant administration of blond psyllium. This was reversed when psyllium was stopped. This interaction may also occur with black psyllium.

Likelihood Probable Evidence D
Metformin (Glucophage)

Theoretically, black psyllium might increase the therapeutic and adverse effects of metformin.
Animal research shows that concurrent consumption of blond psyllium with metformin slows and increases the absorption of metformin. This interaction may also occur with black psyllium. To avoid changes in absorption, take psyllium 30-60 minutes after metformin.

Likelihood Possible Evidence D
Olanzapine (Zyprexa)

Theoretically, taking black psyllium at the same time as olanzapine might reduce olanzapine absorption.
The fiber in black psyllium might decrease the absorption of olanzapine. A single case report describes a reduction in the effectiveness of olanzapine when it was concomitantly administered with an unspecified type of psyllium 3 grams orally twice daily. This effect was reversed when psyllium was stopped.

Likelihood Possible Evidence D
Digoxin (Lanoxin)

Theoretically, taking black psyllium at the same time as digoxin might reduce digoxin absorption and decrease digoxin levels.
Psyllium might bind digoxin in the gut. However, some clinical evidence suggests that psyllium does not impact digoxin absorption.

Likelihood Unlikely Evidence B
Ethinyl Estradiol

Theoretically, taking black psyllium at the same time as ethinyl estradiol might alter levels of estradiol.
Concurrent use of blond psyllium with ethinyl estradiol results in a slight increase in the extent of ethinyl estradiol absorption and a slower rate of absorption. This is unlikely to be clinically significant.

Likelihood Unlikely Evidence D
Oral Drugs

Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Psyllium seems to have variable effects on drug absorption. To avoid changes in absorption, take psyllium 30-60 minutes after oral medications. Animal research shows that blond psyllium delays and increases the absorption of metformin and ethinyl estradiol. Case reports and animal research suggest that blond psyllium might reduce absorption of lithium, digoxin, olanzapine, and carbamazepine. Finally, some pharmacokinetic studies show that psyllium does not affect the absorption of levothyroxine or warfarin. Although many of these studies evaluated blond psyllium, the fiber content in black psyllium may have similar effects.

Likelihood Possible Evidence B
Dietary Fiber full monograph & interactions

Sage14 drug types · 1,296 drugs

Anticholinergic Drugs

Theoretically, sage might decrease the clinical effects of anticholinergic drugs.
In vitro evidence suggests that common sage (Salvia officinalis) and Spanish sage (Salvia lavandulaefolia) can inhibit acetylcholinesterase and might increase acetylcholine levels.

Likelihood Possible Evidence D
Anticonvulsants

Theoretically, sage might interfere with the clinical effects of anticonvulsant drugs.
Some species of sage can cause convulsions when consumed in large quantities.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, taking sage with antidiabetes drugs might increase the risk of hypoglycemia.
In patients with polycystic ovary syndrome (PCOS) or inadequately controlled type 2 diabetes, common sage (Salvia officinalis) has demonstrated hypoglycemic activity. However, other clinical research in patients with inadequately controlled type 2 diabetes shows that common sage extract does not lower fasting blood glucose levels.

Likelihood Possible Evidence B
Antihypertensive Drugs

Theoretically, sage might increase or decrease the effects of antihypertensive drugs.
Animal research suggests that common sage (Salvia officinalis) can cause prolonged blood pressure reduction. However, clinical research suggests that Spanish sage (Salvia lavandulaefolia) can increase blood pressure in some people with hypertension. Until more is known, use with caution.

Likelihood Possible Evidence D
Benzodiazepines

Theoretically, taking sage might increase the sedative and adverse effects of benzodiazepines.
In vitro evidence suggests that certain components of common sage (Salvia officinalis) can bind to benzodiazepine receptors. This effect has not been reported in humans.

Likelihood Possible Evidence D
Cholinergic Drugs

Theoretically, sage might have additive effects when used with cholinergic drugs.
In vitro evidence suggests that common sage (Salvia officinalis) and Spanish sage (Salvia lavandulaefolia) can inhibit acetylcholinesterase and might increase acetylcholine levels.

Likelihood Possible Evidence D
Cns Depressants

Theoretically, taking sage might increase the sedative and adverse effects of CNS depressants.
Some constituents of sage have CNS depressant activity.

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

Theoretically, sage might increase the levels and clinical effects of drugs metabolized by CYP2C19.
In vitro evidence suggests that aqueous extracts of sage can inhibit CYP2C19. So far, this interaction has not been reported in humans.

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

Theoretically, sage might increase the levels and clinical effects of drugs metabolized by CYP2C9.
In vitro evidence suggests that aqueous extracts of sage can inhibit CYP2C9. So far, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2D6 (Cyp2D6) Substrates

Theoretically, sage might increase the levels and clinical effects of drugs metabolized by CYP2D6.
In vitro evidence suggests that aqueous extracts of sage can inhibit CYP2D6. So far, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2E1 (Cyp2E1) Substrates

Theoretically, sage might decrease the levels and clinical effects of drugs metabolized by CYP2E1.
Animal research suggests that drinking common sage (Salvia officinalis) tea increases the expression of CYP2E1. So far, this interaction has not been reported in humans.

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

Theoretically, sage might increase the levels and clinical effects of drugs metabolized by CYP3A4.
In vitro evidence suggests that aqueous extracts of sage can inhibit CYP3A4. So far, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Estrogens

Theoretically, sage might interfere with hormone therapy.
In vitro evidence suggests that geraniol, a constituent of Spanish sage (Salvia lavandulaefolia), exerts estrogenic activity. The clinical significance of this effect is unclear.

Likelihood Possible Evidence D
P-Glycoprotein Substrates

Theoretically, sage might increase levels of drugs transported by P-glycoprotein.
In vitro research suggests that common sage (Salvia officinalis) can inhibit the multi-drug transporter protein, P-glycoprotein. This effect has not been reported in humans.

Likelihood Possible Evidence D
Sage 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

Peppermint5 drug types · 796 drugs

Cyclosporine (Neoral, Sandimmune)

Theoretically, peppermint oil might increase the levels and adverse effects of cyclosporine.
In animal research, peppermint oil inhibits cyclosporine metabolism and increases cyclosporine levels. Inhibition of cytochrome P450 3A4 (CYP3A4) may be partially responsible for this interaction. An interaction between peppermint oil and cyclosporine has not been reported in humans.

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

Theoretically, peppermint might increase the levels of CYP2C19 substrates.
In vitro research shows that peppermint oil inhibits CYP2C19. So far, this interaction has not been reported in humans.

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

Theoretically, peppermint might increase the levels of CYP2C9 substrates.
In vitro research shows that peppermint oil inhibits CYP2C9. So far, this interaction has not been reported in humans.

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

Theoretically, peppermint might increase the levels of CYP3A4 substrates.
Clinical research in healthy volunteers shows that a single dose of peppermint oil 600 mg inhibits CYP3A4 enzymes and increases the AUC of felodipine, a CYP3A4 substrate. However, in vitro research suggests that peppermint oil only inhibits CYP3A4 at very high concentrations.

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

Theoretically, peppermint might increase the levels of CYP1A2 substrates.
In vitro and animal research shows that peppermint oil and peppermint leaf inhibit CYP1A2. However, in clinical research, peppermint tea did not significantly affect the metabolism of caffeine, a CYP1A2 substrate. It is possible that the 6-day duration of treatment may have been too short to identify a difference.

Likelihood Possible Evidence B
Peppermint 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
The maker

Brand information

Manufacturer and brand details for Throat Shield, from the product label.

Gaia Herbs

See all Gaia Herbs products
Name
Aboca S.p.A.
Pharmacist Counseling Corner

Throat Shield by Gaia Herbs: Common Questions

Does Throat Shield by Gaia Herbs interact with any medications?
Yes. Based on its ingredients, Throat Shield has a known interaction with 2,179 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Throat Shield 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 this safe to use while pregnant or breastfeeding?
Peppermint is rated likely safe in pregnancy and lactation. Sage and fennel — both due to their hormone-like compounds — should be avoided in medicinal amounts during pregnancy; food amounts are probably fine. Licorice should be avoided in pregnancy. Marshmallow doesn't have enough safety data; talk with your doctor. For breastfeeding, sage and licorice are best avoided in medicinal amounts.
What's the most common side effect I might notice?
Abdominal discomfort, nausea, or diarrhea are the most commonly reported side effects from the peppermint, sage, and licorice in this blend. Dry mouth or burning in the throat can also occur, especially with sage sprayed in the throat.
Will peppermint in this tea actually make my IBS better?
Peppermint is likely effective for IBS, so yes — there's decent evidence behind that one. For general throat soothing or sore throats, the evidence for marshmallow and the other ingredients is less clear.
Can I take this at the same time as my other medications?
Not always. The mucilage in marshmallow can interfere with oral drug absorption, so space it 30 to 60 minutes after medications. More importantly, multiple ingredients here affect how your liver breaks down drugs — if you take any prescription medications, use the interaction checker on this page with your exact drug names before starting.
What is licorice doing in a throat product?
Licorice has traditionally been used for sore throats and is possibly effective for eczema and mouth sores. But it's also one of the ingredients most likely to cause interactions, especially with heart and blood-thinning drugs, so it's one to be careful about.
Why is there peppermint oil AND peppermint leaf in this?
The two forms provide different delivery — the leaf is gentler (what you'd get in a tea), and the essential oil concentrates the active compounds. Together they may give both flavor and stronger effect, though concentrated oils carry higher interaction and burning risk.

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

Not sure if Throat Shield is safe with your meds?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

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.

Throat Shield label
Go deeper

The Full Monographs Behind Throat Shield’s Ingredients

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

Herb & supplement monograph

Black Psyllium

Interacts with 2,025 drugs

Black psyllium is a soluble-fiber supplement made from the seeds of a Plantago plant, used mostly to ease constipation and support digestive health. It is best known and most studied for rel...

Read the full Black Psyllium monograph → Herb & supplement monograph

Peppermint

Interacts with 796 drugs

Peppermint is a popular herb with the best evidence supporting enteric-coated peppermint oil for easing IBS symptoms. It is generally well tolerated for most adults, but it can cause heartbu...

Read the full Peppermint monograph → Herb & supplement monograph

Sage

Interacts with 1,296 drugs

Sage is a common kitchen herb that is generally safe in food amounts and is traditionally used for sore throats, digestion, sweating, and memory. Some early research is encouraging for sore...

Read the full Sage 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

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

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 →
Sources

Sources & How We Checked

Throat Shield'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 200 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.

Black Psyllium 18 references
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  2. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
  3. Covington TR, et al. Handbook of Nonprescription Drugs. 11th ed. Washington, DC: American Pharmaceutical Association, 1996.
  4. Etman M. Effect of a bulk forming laxative on the bioavailablility of carbamazepine in man. Drug Dev Ind Pharm 1995;21:1901-6.
  5. Perlman BB. Interaction between lithium salts and ispaghula husk. Lancet 1990;335:416.
  6. Vaswani SK, Hamilton RG, Valentine MD, Adkinson NF. Psyllium laxative-induced anaphylaxis, asthma, and rhinitis. Allergy 1996;51:266-8. PubMed
  7. Lantner RR, Espiritu BR, Zumerchik P, Tobin MC. Anaphylaxis following ingestion of a psyllium-containing cereal. JAMA 1990;264:2534-6. DOI
  8. Kaplan MJ. Anaphylactic reaction to "Heartwise." N Engl J Med 1990;323:1072-3. DOI
  9. Nordstrom M, Melander A, Robertsson E, Steen B. Influence of wheat bran and of a bulk-forming ispaghula cathartic on the bioavailability of digoxin in geriatric in-patients. Drug Nutr Interact 1987;5:67-9..
  10. Robinson DS, Benjamin DM, McCormack JJ. Interaction of warfarin and nonsystemic gastrointestinal drugs. Clin Pharmacol Ther 1971;12:491-5. PubMed
  11. Garcia JJ, Fernandez N, Diez MJ, et al. Influence of two dietary fibers in the oral bioavailability and other pharmacokinetic parameters of ethinyloestradiol. Contraception 2000;62:253-7. PubMed
  12. Fernandez N, Lopez C, Díez R, et al. Drug interactions with the dietary fiber Plantago ovata husk. Expert Opin Drug Metab Toxicol 2012;8(11):1377-86.
  13. Semen plantaginis in: WHO Monographs on Selected Medicinal Plants, volume 1. World Health Organization, Geneva, 1999. Available at http://apps.who.int/medicinedocs/en/d/Js2200e/. Accessed November 26, 1026.
  14. Code of Federal Regulations, Title 21 (21CFR 101.17). Food labeling warning, notice, and safe handling statements. Available at www.ecfr.gov/cgi-bin/text-idx?SID=20f647d3b74161501f46564b915b4048&mc=true&node=se21.2.101_117&rgn=div8. Accessed December 3, 2
  15. Code of Federal Regulations, Title 21 (21CFR 201.319). Specific labeling requirements - water-soluble gums, hydrophilic gums, and hydrophilic mucilloids. Available at www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=201.319. Accessed Dece
  16. Diez R, Garcia JJ, Diez MJ, Sierra M, Sahagun AM, Fernandez N. Influence of Plantago ovata husk (dietary fiber) on the bioavailability and other pharmacokinetic parameters of metformin in diabetic rabbits. BMC Complement Altern Med. 2017 Jun 7;17(1):298. PubMed
  17. Chiu AC, Sherman SI. Effects of pharmacological fiber supplements on levothyroxine absorption. Thyroid. 1998;8(8):667-71. PubMed
  18. Merrick C, Madden CA, Capurso NA. A Case of Blunted Orally Disintegrating Olanzapine Effect Due to Coadministered Psyllium. J Clin Psychiatry 2021;82(2):20cr13633. PubMed

See these in context on the Black Psyllium monograph →

Peppermint 41 references
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  2. Pittler MH, Ernst E. Peppermint oil for irritable bowel syndrome: a critical review and metaanalysis. Am J Gastroenterol 1998;93:1131-5. PubMed
  3. Kline RM, Kline JJ, Di Palma J, Barbero GJ. Enteric-coated, pH-dependent peppermint oil capsules for the treatment of irritable bowel syndrome in children. J Pediatr 2001;138:125-8. PubMed
  4. Madisch A, Heydenreich CJ, Wieland V, et al. Treatment of functional dyspepsia with a fixed peppermint oil and caraway oil combination preparation as compared to cisapride. A multicenter, reference-controlled, double-blind equivalence study. Arzneimittel
  5. May B, Kuntz HD, Kieser M, Kohler S. Efficacy of a fixed peppermint oil/caraway oil combination in non-ulcer dyspepsia. Arzneimittelforschung 1996;46:1149-53.
  6. Micklefield GH, Greving I, May B. Effects of peppermint oil and caraway oil on gastroduodenal motility. Phytother Res 2000;14:20-3. DOI
  7. Morton CA, Garioch J, Todd P, et al. Contact sensitivity to menthol and peppermint in patients with intra-oral symptoms. Contact Dermatitis 1995;32:281-4. PubMed
  8. May B, Kohler S, Schneider B. Efficacy and tolerability of a fixed combination of peppermint oil and caraway oil in patients suffering from functional dyspepsia. Aliment Pharmacol Ther 2000;14:1671-7. PubMed
  9. Nash P, Gould SR, Bernardo DE. Peppermint oil does not relieve the pain of irritable bowel syndrome. Br J Clin Pract 1986;40:292-3. DOI
  10. Rees WD, Evans BK, Rhodes J. Treating irritable bowel syndrome with peppermint oil. Br Med J 1979;2:835-6. PubMed
  11. Davies SJ, Harding LM, Baranowski AP. A novel treatment of postherpetic neuralgia using peppermint oil. Clin J Pain 2002;18:200-2. PubMed
  12. Weston CF. Anal burning and peppermint oil. Postgrad Med J 1987;63:717. PubMed
  13. Dresser GK, Wacher V, Wong S, et al. Evaluation of peppermint oil and ascorbyl palmitate as inhibitors of cytochrome P4503A4 activity in vitro and in vivo. Clin Pharmacol Ther 2002;72:247-55. PubMed
  14. Wacher VJ, Wong S, Wong HT. Peppermint oil enhances cyclosporine oral bioavailability in rats: comparison with D-alpha-tocopheryl poly(ethylene glycol 1000) succinate (TPGS) and ketoconazole. J Pharm Sci 2002;91:77-90.
  15. Lawson MJ, Knight RE, Tran K, et al. Failure of enteric-coated peppermint oil in the irritable bowel syndrome: a randomized double-blind crossover study. J Gastroenterol Hepatol 1988;3:235-8. DOI
  16. Unger M, Frank A. Simultaneous determination of the inhibitory potency of herbal extracts on the activity of six major cytochrome P450 enzymes using liquid chromatography/mass spectrometry and automated online extraction. Rapid Commun Mass Spectrom 2004;1 PubMed
  17. Maliakal PP, Wanwimolruk S. Effect of herbal teas on hepatic drug metabolizing enzymes in rats. J Pharm Pharmacol 2001;53:1323-9. PubMed
  18. Rogers SN, Pahor AL. A form of stomatitis induced by excessive peppermint consumption. Dent Update 1995;22:36-7.
  19. Cappello G, Spezzaferro M, Grossi L, et al. Peppermint oil (Mintoil) in the treatment of irritable bowel syndrome: a prospective double blind placebo-controlled randomized trial. Dig Liver Dis 2007;39:530-6. PubMed
  20. Moghadam BK, Gier R, and Thurlow T. Extensive oral mucosal ulcerations caused by misuse of a commercial mouthwash. Cutis 1999;64:131-134.
  21. Andersen, K. E. Contact allergy to toothpaste flavors. Contact Dermatitis 1978;4(4):195-198. PubMed
  22. Barnard, D. R. Repellency of essential oils to mosquitoes (Diptera: Culicidae). J Med Entomol. 1999;36(5):625-629. PubMed
  23. Tamir, S., Davidovich, Z., Attal, P., and Eliashar, R. Peppermint oil chemical burn. Otolaryngol.Head Neck Surg. 2005;133(5):801-802. PubMed
  24. Kalavala, M., Hughes, T. M., Goodwin, R. G., Anstey, A. V., and Stone, N. M. Allergic contact dermatitis to peppermint foot spray. Contact Dermatitis 2007;57(1):57-58. PubMed
  25. Vermaat, H., van Meurs, T., Rustemeyer, T., Bruynzeel, D. P., and Kirtschig, G. Vulval allergic contact dermatitis due to peppermint oil in herbal tea. Contact Dermatitis 2008;58(6):364-365. PubMed
  26. Merat, S., Khalili, S., Mostajabi, P., Ghorbani, A., Ansari, R., and Malekzadeh, R. The effect of enteric-coated, delayed-release peppermint oil on irritable bowel syndrome. Dig.Dis.Sci. 2010;55(5):1385-1390. PubMed
  27. Tran, A., Pratt, M., and DeKoven, J. Acute allergic contact dermatitis of the lips from peppermint oil in a lip balm. Dermatitis 2010;21(2):111-115. DOI
  28. Hitz, Lindenmuller, I and Lambrecht, J. T. Oral care. Curr Probl.Dermatol 2011;40:107-115.
  29. Shavakhi, A., Ardestani, S. K., Taki, M., Goli, M., and Keshteli, A. H. Premedication with peppermint oil capsules in colonoscopy: a double blind placebo-controlled randomized trial study. Acta Gastroenterol Belg 2012;75(3):349-353.
  30. Lech, Y., Olesen, K. M., Hey, H., Rask-Pedersen, E., Vilien, M., and Ostergaard, O. [Treatment of irritable bowel syndrome with peppermint oil. A double- blind study with a placebo]. Ugeskr.Laeger 10-3-1988;150(40):2388-2389.
  31. Parys, B. T. Chemical burns resulting from contact with peppermint oil mar: a case report. Burns Incl.Therm.Inj. 1983;9(5):374-375. PubMed
  32. Bayat R, Borici-Mazi R. A case of anaphylaxis to peppermint. Allergy Asthma Clin Immunol. 2014;10(1):6. PubMed
  33. Rich G, Shah A, Koloski N, et al. A randomized placebo-controlled trial on the effects of Menthacarin, a proprietary peppermint- and caraway-oil-preparation, on symptoms and quality of life in patients with functional dyspepsia. Neurogastroenterol Motil 2 PubMed
  34. Douros A, Bronder E, Andersohn F, et al. Herb-Induced Liver Injury in the Berlin Case-Control Surveillance Study. Int J Mol Sci 2016;17(1). PubMed
  35. Begas E, Tsioutsiouliti A, Kouvaras E, et al. Effects of peppermint tea consumption on the activities of CYP1A2, CYP2A6, Xanthine Oxidase, N-acetyltranferase-2 and UDP-glucuronosyltransferases-1A1/1A6 in healthy volunteers. Food Chem Toxicol 2017;100:80-9 PubMed
  36. Cash BD, Epstein MS, Shah SM. A Novel Delivery System of Peppermint Oil Is an Effective Therapy for Irritable Bowel Syndrome Symptoms. Dig Dis Sci 2016;61(2):560-71. PubMed
  37. Elsaie LT, El Mohsen AM, Ibrahim IM, Mohey-Eddin MH, Elsaie ML. Effectiveness of topical peppermint oil on symptomatic treatment of chronic pruritus. Clin Cosmet Investig Dermatol 2016;9:333-8. PubMed
  38. Wu J, Xu R, Zhan R, et al. Effective symptomatic treatment for severe and intractable pruritus associated with severe burn-induced hypertrophic scars: A prospective, multicenter, controlled trial. Burns 2016;42(5):1059-66. PubMed
  39. Weerts ZZRM, Masclee AAM, Witteman BJM, et al. Efficacy and safety of peppermint oil in a randomized, double-blind trial of patients with irritable bowel syndrome. Gastroenterology. 2020;158(1):123-136. PubMed
  40. Nee J, Ballou S, Kelley JM, et al. Peppermint Oil Treatment for Irritable Bowel Syndrome: A Randomized Placebo-Controlled Trial. Am J Gastroenterol 2021;116(11):2279-2285. PubMed
  41. Ingrosso MR, Ianiro G, Nee J, et al. Systematic review and meta-analysis: efficacy of peppermint oil in irritable bowel syndrome. Aliment Pharmacol Ther 2022;56(6):932-41. PubMed

See these in context on the Peppermint monograph →

Sage 27 references
  1. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  2. Todorov S, Philianos S, Petkov V, et al. Experimental pharmacological study of three species from genus Salvia. Acta Physiol Pharmacol (Bulg) 1984;10:13-20.
  3. Perry NS, Bollen C, Perry EK, Ballard C. Salvia for dementia therapy: review of pharmacological activity and pilot tolerability clinical trial. Pharmacol Biochem Behav 2003;75:651-9.. PubMed
  4. Saller R, Buechi S, Meyrat R, Schmidhauser C. Combined herbal preparation for topical treatment of Herpes labialis. Forsch Komplementarmed Klass Naturheilkd 2001;8:373-82. PubMed
  5. Akhondzadeh S, Noroozian M, Mohammadi M, et al. Salvia officinalis extract in the treatment of patients with mild to moderate Alzheimer's disease: a double blind, randomized and placebo-controlled trial. J Clin Pharm Ther 2003;28:53-9.
  6. Perry NB, Anderson RE, Brennan NJ, et al. Essential oils from dalmatian sage (Salvia officinalis l.): variations among individuals, plant parts, seasons, and sites. J Agric Food Chem 1999;47:2048-54..
  7. Foster BC, Vandenhoek S, Hana J, et al. In vitro inhibition of human cytochrome P450-mediated metabolism of marker substrates by natural products. Phytomedicine 2003;10:334-42.. PubMed
  8. Burkhard PR, Burkhardt K, Haenggeli CA, Landis T. Plant-induced seizures: reappearance of an old problem. J Neurol 1999;246:667-70. PubMed
  9. Bommer S, Klein P, Suter A. First time proof of sage's tolerability and efficacy in menopausal women with hot flushes. Adv Ther 2011;28:490-500. PubMed
  10. Hellum BH, Nilsen OG. The in vitro inhibitory potential of trade herbal products on human CYP2D6-mediated metabolism and the influence of ethanol. Basic Clin Pharmacol Toxicol. 2007 Nov;101:350-8.
  11. Orhan, I., Kartal, M., Kan, Y., and Sener, B. Activity of essential oils and individual components against acetyl- and butyrylcholinesterase. Z.Naturforsch.C. 2008;63(7-8):547-553.
  12. Perry, N. S., Houghton, P. J., Theobald, A., Jenner, P., and Perry, E. K. In-vitro inhibition of human erythrocyte acetylcholinesterase by salvia lavandulaefolia essential oil and constituent terpenes. J Pharm Pharmacol 2000;52(7):895-902.
  13. Perry, N. S., Houghton, P. J., Sampson, J., Theobald, A. E., Hart, S., Lis-Balchin, M., Hoult, J. R., Evans, P., Jenner, P., Milligan, S., and Perry, E. K. In-vitro activity of S. lavandulaefolia (Spanish sage) relevant to treatment of Alzheimer's diseas
  14. Futrell, J. M. and Rietschel, R. L. Spice allergy evaluated by results of patch tests. Cutis 1993;52(5):288-290.
  15. Kavvadias, D., Monschein, V., Sand, P., Riederer, P., and Schreier, P. Constituents of sage (Salvia officinalis) with in vitro affinity to human brain benzodiazepine receptor. Planta Med. 2003;69(2):113-117.
  16. Savelev, S. U., Okello, E. J., and Perry, E. K. Butyryl- and acetyl-cholinesterase inhibitory activities in essential oils of Salvia species and their constituents. Phytother Res 2004;18(4):315-324.
  17. Kennedy, D. O., Pace, S., Haskell, C., Okello, E. J., Milne, A., and Scholey, A. B. Effects of cholinesterase inhibiting sage (Salvia officinalis) on mood, anxiety and performance on a psychological stressor battery. Neuropsychopharmacology 2006;31(4):84 PubMed
  18. Hubbert, M., Sievers, H., Lehnfeld, R., and Kehrl, W. Efficacy and tolerability of a spray with Salvia officinalis in the treatment of acute pharyngitis - a randomised, double-blind, placebo-controlled study with adaptive design and interim analysis. Eur
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  20. Hellum, B. H. and Nilsen, O. G. In vitro inhibition of CYP3A4 metabolism and P-glycoprotein-mediated transport by trade herbal products. Basic Clin Pharmacol Toxicol. 2008;102(5):466-475.
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  23. Sertoli, A., Fabbri, P., Campolmi, P., and Panconesi, E. Allergic contact dermatitis to Salvia Officinalis, Inula Viscosa and Conyza Bonariensis. Contact Dermatitis 1978;4(5):314-315.
  24. Vandecasteele K, Ost P, Oosterlinck W, et al. Evaluation of the efficacy and safety of Salvia officinalis in controlling hot flashes in prostate cancer patients treated with androgen deprivation. Phytother Res. 2012;26(2):208-13.
  25. Kianbakht S, Dabaghian FH. Improved glycemic control and lipid profile in hyperlipidemic type 2 diabetic patients consuming Salvia officinalis L. leaf extract: a randomized placebo. Controlled clinical trial. Complement Ther Med. 2013;21(5):441-6. PubMed
  26. Amini L, Mojab F, Jahanfar S, Sepidarkish M, Raoofi Z, Maleki-Hajiagha A. Efficacy of Salvia officinalis extract on the prevention of insulin resistance in euglycemic patients with polycystic ovary syndrome: A double-blinded placebo-controlled clinical tr
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See these in context on the Sage 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
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See these in context on the Licorice 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.

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